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omr-ws-54cc4ae5ce96c6df57ba48584e4787d95125f86f3302590ef32fafd34b28b144
Wayne, Bryson, and Young are engaged in a Nerf gun game. On a given player’s turn, he has the option of shooting once at one of his opponents. If he successfully hits them, they are removed from the game. Wayne has a 20% chance of hitting his target, Bryson has a 70% chance of hitting his target, and Young never misses...
[ "\\dfrac{1003}{4750}" ]
[ "Wayne, Bryson, and Young are engaged in a Nerf gun game. On a given player’s turn, he has the option of shooting once at one of his opponents. If he successfully hits them, they are removed from the game. Wayne has a 20% chance of hitting his target, Bryson has a 70% chance of hitting his target, and Young never m...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 9, "genselect": 6 }
15
0
0
omr-ws-c78656865b6668e3be3f0943a4741269774cf18442e9d058ee67557aac3627d6
Wayne, Bryson, and Young are engaged in a Nerf gun game. On a given player’s turn, he has the option of shooting once at one of his opponents. Wayne has a 20% chance of hitting his target, Bryson has a 70% chance of hitting his target, and Young never misses. If Wayne goes first, then Bryson, then Young, repeating that...
[ "0.1" ]
[ "Wayne, Bryson, and Young are engaged in a Nerf gun game. On a given player’s turn, he has the option of shooting once at one of his opponents. Wayne has a 20% chance of hitting his target, Bryson has a 70% chance of hitting his target, and Young never misses. If Wayne goes first, then Bryson, then Young, repeating...
[ "aops_c4_high_school_math" ]
[ "tir" ]
{ "tir": 2 }
2
0
0
omr-ws-8d880fde647582960a3b8289ce38a30646b89a247dfc1309659ac210719e457b
We are allowed to remove exactly one integer from the list $$-1,0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11,$$and then we choose two distinct integers at random from the remaining list. What number should we remove if we wish to maximize the probability that the sum of the two chosen numbers is 10?
[ "5" ]
[ "We are allowed to remove exactly one integer from the list $$-1,0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11,$$and then we choose two distinct integers at random from the remaining list. What number should we remove if we wish to maximize the probability that the sum of the two chosen numbers is 10?" ]
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-431e31ba8cde86ffdadf7eaac39daad10a9cf1ede5a92ed04d9c5be8d9a11aaa
We are colouring numbers from 1 to 10 with red and blue colours. For every \( k = 1, 2, \ldots, a \), the subtraction of two numbers that have the same color is \( k \), and this situation is valid for both red and blue. What is the biggest value of \( a \)?
[ "4" ]
[ "We are colouring numbers from 1 to 10 with red and blue colours. For every \\( k = 1, 2, \\ldots, a \\), the subtraction of two numbers that have the same color is \\( k \\), and this situation is valid for both red and blue. What is the biggest value of \\( a \\)?" ]
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-8a07aaa506289b7803cd987bf9de930388aa9c3daf727fd359552c19d2299628
We are given $2n+1$ real numbers $a_1, a_2, \ldots, a_{2n+1}$. It is known that if we remove any one of these numbers, the remaining $2n$ numbers can be rearranged into two $n$-element groups with equal sums. Calculate the value of $a_1 + a_2 + \cdots + a_{2n+1}$ given that $n=4$.
[ "0" ]
[ "We are given $2n+1$ real numbers $a_1, a_2, \\ldots, a_{2n+1}$. It is known that if we remove any one of these numbers, the remaining $2n$ numbers can be rearranged into two $n$-element groups with equal sums. Calculate the value of $a_1 + a_2 + \\cdots + a_{2n+1}$ given that $n=4$." ]
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-6d30e940eec428d1b446ccd5cdd16b1a3a39b871a15a7673659396b734c175d0
We are given $b$ white balls and $n$ black balls ($b,n>0$) which are to be distributed among two urns, at least one in each. Let $s$ be the number of balls in the first urn, and $r$ the number of white ones among them. One randomly chooses an urn and randomly picks a ball from it. Compute the probability $p$ that the d...
[ "\\dfrac{r}{2s} + \\dfrac{b - r}{2(b + n - s)}" ]
[ "We are given $b$ white balls and $n$ black balls ($b,n>0$) which are to be distributed among two urns, at least one in each. Let $s$ be the number of balls in the first urn, and $r$ the number of white ones among them. One randomly chooses an urn and randomly picks a ball from it. Compute the probability $p$ that ...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 15 }
15
0
0
omr-ws-90b43d47da41b7180486a48b3bc300d72de299355c28f24d758d3d19a4b4c187
We are given 5040 balls in \( k \) different colors, where the number of balls of each color is the same. The balls are put into 2520 bags so that each bag contains two balls of different colors. Find the smallest \( k \) such that, however the balls are distributed into the bags, we can arrange the bags around a circl...
[ "8" ]
[ "We are given 5040 balls in \\( k \\) different colors, where the number of balls of each color is the same. The balls are put into 2520 bags so that each bag contains two balls of different colors. Find the smallest \\( k \\) such that, however the balls are distributed into the bags, we can arrange the bags aroun...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 8 }
19
0
0
omr-ws-e7cca4f63e59646d148bbfe6c93a6e5a9524fecbad51d44d5a93913cc9e47c93
We are given 5771 weights weighing 1, 2, 3, ..., 5770, 5771. We partition the weights into $n$ sets of equal weight. What is the maximal $n$ for which this is possible?
[ "2886" ]
[ "We are given 5771 weights weighing 1, 2, 3, ..., 5770, 5771. We partition the weights into $n$ sets of equal weight. What is the maximal $n$ for which this is possible?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 44, "genselect": 8, "tir": 21 }
73
0
0
omr-ws-16010ca3ad66b5c6a9dcce506cf3bbf1e3efabff5eb789292f5ad699cf3b8685
We are given 6 boxes (arranged in a line from left to right) and 5 distinct balls. The balls are placed in some or all of the first 5 boxes (and hence there is a total of \(5^5\) ways of arranging them). We apply the following rule repeatedly, until none of the first five boxes has more than one ball in it: If a box ha...
[ "1296" ]
[ "We are given 6 boxes (arranged in a line from left to right) and 5 distinct balls. The balls are placed in some or all of the first 5 boxes (and hence there is a total of \\(5^5\\) ways of arranging them). We apply the following rule repeatedly, until none of the first five boxes has more than one ball in it: If a...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-6245faf4ac04ef5636c2cf0b0c31ed5dbc702da85e8b7bf9896d6c082f362ff2
We are given 6 boxes arranged in a line from left to right and 5 distinct balls. The balls are placed in some or all of the first 5 boxes (resulting in a total of $5^5$ ways to arrange them). We apply the following rule repeatedly until none of the first 5 boxes has more than one ball in it: if a box has more than one ...
[ "1296" ]
[ "We are given 6 boxes arranged in a line from left to right and 5 distinct balls. The balls are placed in some or all of the first 5 boxes (resulting in a total of $5^5$ ways to arrange them). We apply the following rule repeatedly until none of the first 5 boxes has more than one ball in it: if a box has more than...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 44, "genselect": 8, "tir": 11 }
63
0
0
omr-ws-17ffa3a26fbc6fbaa821870133201593e5e4c171ed8d4024113169cbeef04260
We are given a $4\times4$ square, consisting of $16$ squares with side length of $1$. Every $1\times1$ square inside the square has a non-negative integer entry such that the sum of any five squares that can be covered with the figures (the figures can be moved and rotated) equals $5$. What is the greatest number of di...
[ "3" ]
[ "We are given a $4\\times4$ square, consisting of $16$ squares with side length of $1$. Every $1\\times1$ square inside the square has a non-negative integer entry such that the sum of any five squares that can be covered with the figures (the figures can be moved and rotated) equals $5$. What is the greatest numbe...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-f9b6e5343a56d0f9cb6ae065d045d9b1ba68ce81d76abce4e212691f2e2125d6
We are given a 12-pint vessel filled with a liquid and two empty vessels with capacities of 9 pints and 5 pints, with no markings on any of them. How many total possible transfers are needed to divide the liquid into two equal portions, given that no container should be empty during the process before reaching equal po...
[ "12" ]
[ "We are given a 12-pint vessel filled with a liquid and two empty vessels with capacities of 9 pints and 5 pints, with no markings on any of them. How many total possible transfers are needed to divide the liquid into two equal portions, given that no container should be empty during the process before reaching equ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 1 }
11
0
0
omr-ws-5ede40df7e6d4ddff6642f0be4392520e058ac6916bd7b69113a30131a137ccb
We are given a 12-pint vessel filled with a liquid and two empty vessels with capacities of 9 pints and 5 pints, with no markings on any of them. How many total possible transfers are needed to divide the liquid into two equal portions?
[ "8" ]
[ "We are given a 12-pint vessel filled with a liquid and two empty vessels with capacities of 9 pints and 5 pints, with no markings on any of them. How many total possible transfers are needed to divide the liquid into two equal portions?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 13, "genselect": 8 }
21
0
0
omr-ws-7bbd8ba0c6cda8a7edb46cb10b8319817904b711611bc8f6328c878fac4d80ce
We are given a certain number of identical sets of weights; each set consists of four different weights expressed by natural numbers. Using these weights, we are able to weigh out every integer mass up to $1985$ (inclusive). How many ways are there to compose such a set of weight sets given that the joint mass of all w...
[ "1" ]
[ "We are given a certain number of identical sets of weights; each set consists of four different weights expressed by natural numbers. Using these weights, we are able to weigh out every integer mass up to $1985$ (inclusive). How many ways are there to compose such a set of weight sets given that the joint mass of ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 5 }
15
0
0
omr-ws-06801c67af6b671c0b273afd9e7382e7b321242efeb5b1ba398c36c4c2e079b8
We are given a combination lock consisting of 6 rotating discs. Each disc consists of digits \(0, 1, 2, \ldots, 9\) in that order (after digit 9 comes 0). The lock is opened by exactly one combination. A move consists of turning one of the discs one digit in any direction, and the lock opens instantly if the current co...
[ "29" ]
[ "We are given a combination lock consisting of 6 rotating discs. Each disc consists of digits \\(0, 1, 2, \\ldots, 9\\) in that order (after digit 9 comes 0). The lock is opened by exactly one combination. A move consists of turning one of the discs one digit in any direction, and the lock opens instantly if the cu...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 14 }
14
0
0
omr-ws-066e4f4d850ad65f765dca364bc49a550691b508b02f676600cd5f3fec07b460
We are given a fixed point on the circle of radius 1, and going from this point along the circumference in the positive direction on curved distances \(0, 1, 2, \ldots\) from it we obtain points with abscissas \(n = 0, 1, 2, \ldots\). How many points among them should we take to ensure that some two of them are less th...
[ "33" ]
[ "We are given a fixed point on the circle of radius 1, and going from this point along the circumference in the positive direction on curved distances \\(0, 1, 2, \\ldots\\) from it we obtain points with abscissas \\(n = 0, 1, 2, \\ldots\\). How many points among them should we take to ensure that some two of them ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 3 }
14
0
0
omr-ws-a5ec59ce0077d215bba2f64480ba73b61345725d11f05673175b32b13b441588
We are given a map divided into $13 \times 13$ fields. A tank is stationed at one of these fields and must be hit twice to be destroyed. After the first hit, the tank moves to a neighboring field. How many shots must be fired to ensure the tank is destroyed, given that we cannot see the tank or receive any feedback reg...
[ "247" ]
[ "We are given a map divided into $13 \\times 13$ fields. A tank is stationed at one of these fields and must be hit twice to be destroyed. After the first hit, the tank moves to a neighboring field. How many shots must be fired to ensure the tank is destroyed, given that we cannot see the tank or receive any feedba...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-2d8c987e41ef988c28f9eb15c8be38301208c3ceecd347859ab46a3671b825bf
We are given a square of side length 1 with a lower left vertex at the origin of the Cartesian plane and sides parallel to the axes. We find the midpoint of the right side of the square and connect it to the midpoint of the opposite segment. Then we find the midpoint of the newly created segment and connect it to the m...
[ "\\(\\left(\\frac{2}{3}, \\frac{1}{3}\\right)\\)" ]
[ "We are given a square of side length 1 with a lower left vertex at the origin of the Cartesian plane and sides parallel to the axes. We find the midpoint of the right side of the square and connect it to the midpoint of the opposite segment. Then we find the midpoint of the newly created segment and connect it to ...
[ "aops_c4_high_school_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-ceda5cc9706d893f3eccd9191c4a1e127228871fbbbc6c77963f665e9b8a2043
We are given an infinite deck of cards, each with a real number on it. For every real number \( x \), there is exactly one card in the deck that has \( x \) written on it. Two players draw disjoint sets \( A \) and \( B \) of 100 cards each from this deck. Define a rule that declares one of them a winner, satisfying th...
[ "100" ]
[ "We are given an infinite deck of cards, each with a real number on it. For every real number \\( x \\), there is exactly one card in the deck that has \\( x \\) written on it. Two players draw disjoint sets \\( A \\) and \\( B \\) of 100 cards each from this deck. Define a rule that declares one of them a winner, ...
[ "aops_c6_high_school_olympiads" ]
[ "genselect" ]
{ "genselect": 5 }
5
0
0
omr-ws-589d4ba7c03ed028ed94fa5acb6cfcfc2381dc8559e9d66750f2832ea757b465
We are given an infinite sequence of $1$'s and $2$'s with the following properties: - The first element of the sequence is $1$. - There are no two consecutive $2$'s or three consecutive $1$'s. - If we replace consecutive $1$'s by a single $2$, leave the single $1$'s alone, and delete the original $2$'s, then we recover...
[ "\\(\\lfloor (\\sqrt{2} - 1) n + (1 - \\frac{\\sqrt{2}}{2}) \\rfloor\\)" ]
[ "We are given an infinite sequence of $1$'s and $2$'s with the following properties:\n- The first element of the sequence is $1$.\n- There are no two consecutive $2$'s or three consecutive $1$'s.\n- If we replace consecutive $1$'s by a single $2$, leave the single $1$'s alone, and delete the original $2$'s, then we...
[ "aops_c7_college_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-84f93350e836971cc99ab11e698380a70f74a7033885f7ab6dd12767eec3b7ca
We are given some three-element subsets of $\{1,2, \dots ,n\}$ such that any two of them have at most one common element. A subset of $\{1,2, \dots ,n\}$ is called [i]nice[/i] if it does not include any of the given three-element subsets. If no matter how the three-element subsets are selected initially, we can add one...
[ "436" ]
[ "We are given some three-element subsets of $\\{1,2, \\dots ,n\\}$ such that any two of them have at most one common element. A subset of $\\{1,2, \\dots ,n\\}$ is called [i]nice[/i] if it does not include any of the given three-element subsets. If no matter how the three-element subsets are selected initially, we ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 46, "genselect": 6, "tir": 3 }
55
0
0
omr-ws-735523c7447572b7db938af5567ac93ad49e9ed23ecc56f873c75f68b64896ab
We are given sufficiently many tiles of the forms of a $2 \times 1$ rectangle and $1 \times 1$ square. Let $n > 3$ be a rational number. In how many ways can one tile a rectangle $3 \times n$ using these tiles, so that no two $2 \times 1$ rectangles have overlaps (their borders are adjacent), and each of them has the l...
[ "3^n" ]
[ "We are given sufficiently many tiles of the forms of a $2 \\times 1$ rectangle and $1 \\times 1$ square. Let $n > 3$ be a rational number. In how many ways can one tile a rectangle $3 \\times n$ using these tiles, so that no two $2 \\times 1$ rectangles have overlaps (their borders are adjacent), and each of them ...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 12, "genselect": 3 }
15
0
0
omr-ws-8970bf5558b31006cc23f191eecb66ae50df31ac3a2b97d86925b6d23c3c48f5
We are given that $$54+(98\div14)+(23\cdot 17)-200-(312\div 6)=200.$$Now, let's remove the parentheses: $$54+98\div14+23\cdot 17-200-312\div 6.$$What does this expression equal?
[ "200" ]
[ "We are given that $$54+(98\\div14)+(23\\cdot 17)-200-(312\\div 6)=200.$$Now, let's remove the parentheses: $$54+98\\div14+23\\cdot 17-200-312\\div 6.$$What does this expression equal?" ]
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-89f7b5826b248237920084e98b05b6f5ea7ec013642af2f1994b47e62c282e23
We are given two mutually tangent circles in the plane, with radii \( r_1 \) and \( r_2 \). A line intersects these circles in four points, determining three segments of equal length. Find this length as a function of \( r_1 \) and \( r_2 \) and the condition for the solvability of the problem.
[ "\\(\\frac{2 \\sqrt{r_1 r_2}}{r_1 + r_2}\\)" ]
[ "We are given two mutually tangent circles in the plane, with radii \\( r_1 \\) and \\( r_2 \\). A line intersects these circles in four points, determining three segments of equal length. Find this length as a function of \\( r_1 \\) and \\( r_2 \\) and the condition for the solvability of the problem." ]
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-c16b5b9478ce80a286957ef82ad1eec0b24eb2a8a9d5d37d80813402f34a5d13
We are grouping the numbers $1, 2, 3, \ldots, 100$ into ten groups. We delete the two smallest numbers from each group and then delete the smallest ten numbers from the remaining numbers. What is the smallest possible value of the smallest number after these deletions?
[ "13" ]
[ "We are grouping the numbers $1, 2, 3, \\ldots, 100$ into ten groups. We delete the two smallest numbers from each group and then delete the smallest ten numbers from the remaining numbers. What is the smallest possible value of the smallest number after these deletions?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 1, "genselect": 2 }
3
0
0
omr-ws-a6f9f95067d12d67dfb06d388c158e6ef5defd4af4a6af74ddbf317a0bdf7e59
We are looking for a treasure hidden under one of the tiles covering a room. Each time a tile is picked up and the treasure is not found, the direction to the treasure appears on the tile. Given that the treasure can be found by picking up $n$ tiles, determine the maximum number of tiles that can cover the room.
[ "\\(2^n\\)" ]
[ "We are looking for a treasure hidden under one of the tiles covering a room. Each time a tile is picked up and the treasure is not found, the direction to the treasure appears on the tile. Given that the treasure can be found by picking up $n$ tiles, determine the maximum number of tiles that can cover the room." ...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-1191730da1c95f673c64e4c19e702f06949c1c81a448a539360a4ada5c016089
We are numbering the rows and columns of a $29 \times 29$ chessboard with numbers $1, 2, \ldots, 29$ (top row numbered $1$ and first column numbered $1$). We select some squares such that for each selected square, there is at most one other selected square with both row and column numbers greater than or equal to those...
[ "43" ]
[ "We are numbering the rows and columns of a $29 \\times 29$ chessboard with numbers $1, 2, \\ldots, 29$ (top row numbered $1$ and first column numbered $1$). We select some squares such that for each selected square, there is at most one other selected square with both row and column numbers greater than or equal t...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-9638de52ef94629d9a5931781cda65b048a1afa7808a8b748c1a7d6a4632f926
We are placing \( n \) integers whose sum is 94 over a circle such that each number is equal to the absolute value of the difference of the next two numbers (clockwise). What is the largest \( n \) that makes such placement possible?
[ "141" ]
[ "We are placing \\( n \\) integers whose sum is 94 over a circle such that each number is equal to the absolute value of the difference of the next two numbers (clockwise). What is the largest \\( n \\) that makes such placement possible?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 15, "genselect": 8 }
23
0
0
omr-ws-e2a58141850b7eb71161447d96ca1e826dbdc1eb754f94ec24a96d5838d51f32
We are splitting a giant cake for 2020 persons as follows: The first person takes $\frac{1}{2020}$ of the cake, the second person takes $\frac{2}{2020}$ of the remaining cake, the third person takes $\frac{3}{2020}$ of the remaining cake, and so on, until the $2019^{\text{th}}$ person takes $\frac{2019}{2020}$ of the r...
[ "45th guest" ]
[ "We are splitting a giant cake for 2020 persons as follows: The first person takes $\\frac{1}{2020}$ of the cake, the second person takes $\\frac{2}{2020}$ of the remaining cake, the third person takes $\\frac{3}{2020}$ of the remaining cake, and so on, until the $2019^{\\text{th}}$ person takes $\\frac{2019}{2020}...
[ "aops_c4_high_school_math", "c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 12 }
28
0
0
omr-ws-c1b5c1ae8051cc5c5b9375e4aba86b03f47fa499b82efecad64078c19e5b6a3d
We are writing either $0$ or $1$ to unit squares of an $8 \times 8$ chessboard. If the sum of numbers is even vertically, horizontally, or diagonally, what is the greatest possible value of the sum of all numbers on the board?
[ "48" ]
[ "We are writing either $0$ or $1$ to unit squares of an $8 \\times 8$ chessboard. If the sum of numbers is even vertically, horizontally, or diagonally, what is the greatest possible value of the sum of all numbers on the board?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 4, "genselect": 2, "tir": 3 }
9
0
0
omr-ws-8b50c24b8a28ba9bc9c4b4a7f86589a2ce53ab7b77eb6ac689ff11a4967cb7ec
We arrange \( n \) boys and \( n \) girls in one row. Let \( A \) be the number of arrangements that cannot be split into two parts such that each part has an equal number of boys and girls. Let \( B \) be the number of arrangements that can be split into two parts with an equal number of boys and girls in exactly one ...
[ "2" ]
[ "We arrange \\( n \\) boys and \\( n \\) girls in one row. Let \\( A \\) be the number of arrangements that cannot be split into two parts such that each part has an equal number of boys and girls. Let \\( B \\) be the number of arrangements that can be split into two parts with an equal number of boys and girls in...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 6 }
6
0
0
omr-ws-0d9babd848d927a74b9e531f3131f25dba12edb539b3f37c53113dd323c42ca1
We arrange the numbers $1, 2, 3, \ldots, 16$ in a $4 \times 4$ board such that the numbers $1, 2, \ldots, 4$ appear in the first row in increasing order, $5, 6, \ldots, 8$ in the second row in increasing order, and so on. Every minute, we can take a number in a square, subtract 2 from it, and add 1 to each of two neigh...
[ "\\dfrac{16!}{2}" ]
[ "We arrange the numbers $1, 2, 3, \\ldots, 16$ in a $4 \\times 4$ board such that the numbers $1, 2, \\ldots, 4$ appear in the first row in increasing order, $5, 6, \\ldots, 8$ in the second row in increasing order, and so on. Every minute, we can take a number in a square, subtract 2 from it, and add 1 to each of ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 4, "genselect": 4 }
8
0
0
omr-ws-fed7b5df035b3bed0484b0c4872dfa445b4d47ab2dda00a7e2554d377b389050
We attach the numbers $1$, $0$, $0$, $0$, $0$, $0$ to the vertices of a regular hexagon. We are allowed to transform the numbers using the following rules: - (a) Add an arbitrary integer to the numbers at two opposite vertices. - (b) Add an arbitrary integer to the numbers at three vertices forming an equilateral trian...
[ "2" ]
[ "We attach the numbers $1$, $0$, $0$, $0$, $0$, $0$ to the vertices of a regular hexagon. We are allowed to transform the numbers using the following rules:\n- (a) Add an arbitrary integer to the numbers at two opposite vertices.\n- (b) Add an arbitrary integer to the numbers at three vertices forming an equilatera...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 3, "genselect": 3 }
6
0
0
omr-ws-55b0f7bfdd75cd7043fb123bc278b4c4a2aed8bd16c8ff64c35619eb0d63f22a
We begin with an equilateral triangle with side length 1. We divide each side into three segments of equal length, and add an equilateral triangle to each side using the middle third as a base. We then repeat this process indefinitely. What is the area of the resulting figure?
[ "\\(\\frac{9\\sqrt{3}}{20}\\)" ]
[ "We begin with an equilateral triangle with side length 1. We divide each side into three segments of equal length, and add an equilateral triangle to each side using the middle third as a base. We then repeat this process indefinitely. What is the area of the resulting figure?" ]
[ "aops_c4_high_school_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-bc270a4ea83855000bb1606f8262f3768d485ad40acddfb51a05ca5aef07ec49
We build a tower of $2 \times 1$ dominoes such that each story consists of $55$ dominoes covering a $10 \times 11$ rectangle. The tower is called [i]stable[/i] if for every non-lattice point of the $10 \times 11$ rectangle, there is a domino that has an inner point above it. How many stories is the lowest [i]stable[/i]...
[ "5" ]
[ "We build a tower of $2 \\times 1$ dominoes such that each story consists of $55$ dominoes covering a $10 \\times 11$ rectangle. The tower is called [i]stable[/i] if for every non-lattice point of the $10 \\times 11$ rectangle, there is a domino that has an inner point above it. How many stories is the lowest [i]st...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-49e19be45f573c38d78a9dda510b3f61ecd10fdfa101d73988306a62e0830632
We call $A_{1}, A_{2}, A_{3}$ *mangool* if there is a permutation $\pi$ such that $A_{\pi(2)} \not\subset A_{\pi(1)}$ and $A_{\pi(3)} \not\subset A_{\pi(1)} \cup A_{\pi(2)}$. A good family is a family of finite subsets of $\mathbb{N}$ like $X, A_{1}, A_{2}, \dots, A_{n}$. To each good family, we correspond a graph with...
[ "All graphs can be represented by a good family." ]
[ "We call $A_{1}, A_{2}, A_{3}$ *mangool* if there is a permutation $\\pi$ such that $A_{\\pi(2)} \\not\\subset A_{\\pi(1)}$ and $A_{\\pi(3)} \\not\\subset A_{\\pi(1)} \\cup A_{\\pi(2)}$. A good family is a family of finite subsets of $\\mathbb{N}$ like $X, A_{1}, A_{2}, \\dots, A_{n}$. To each good family, we corre...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 12, "tir": 1 }
13
0
0
omr-ws-dcb6f8ec974f27648df534c31926f2b4353cbe1da8e6a5065759134f942fe5f1
We call a $6 \times 6$ table consisting of zeros and ones [i]right[/i] if the sum of the numbers in each row and each column is equal to $3$. Two right tables are called [i]similar[/i] if one can get from one to the other by successive interchanges of rows and columns. Find the largest possible size of a set of pairwis...
[ "518400" ]
[ "We call a $6 \\times 6$ table consisting of zeros and ones [i]right[/i] if the sum of the numbers in each row and each column is equal to $3$. Two right tables are called [i]similar[/i] if one can get from one to the other by successive interchanges of rows and columns. Find the largest possible size of a set of p...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 13, "genselect": 7 }
20
0
0
omr-ws-b603a812361b05055563a0f8e07fa86087126d6c52357522235d5ca1e460a358
We call a coloring of an \(m \times n\) table (\(m, n \geq 5\)) in three colors a good coloring if the following two conditions are satisfied: (i) Each cell has the same number of neighboring cells of two other colors. (ii) Each corner cell has no neighboring cells of its color. Find all pairs \((m, n)\) for which ther...
[ "(m, n) \\text{ with both } m \\text{ and } n \\text{ even}" ]
[ "We call a coloring of an \\(m \\times n\\) table (\\(m, n \\geq 5\\)) in three colors a good coloring if the following two conditions are satisfied:\n(i) Each cell has the same number of neighboring cells of two other colors.\n(ii) Each corner cell has no neighboring cells of its color.\nFind all pairs \\((m, n)\\...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 4 }
14
0
0
omr-ws-fe85ae229756b6b48853efb08f614f59b89a1b20a9fcf1eb99dfa95b26448b2f
We call a family of vectors \( v_1, \ldots, v_k \) "nice" if every vector in \( \mathbb{R}^n \) can be written as a linear combination of \( v_i \) with strictly positive coefficients. Find the best \( k_n \) such that any nice family with \( k_n \) vectors contains a proper subfamily which is also nice.
[ "\\(2n\\)" ]
[ "We call a family of vectors \\( v_1, \\ldots, v_k \\) \"nice\" if every vector in \\( \\mathbb{R}^n \\) can be written as a linear combination of \\( v_i \\) with strictly positive coefficients. Find the best \\( k_n \\) such that any nice family with \\( k_n \\) vectors contains a proper subfamily which is also n...
[ "aops_c7_college_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-a02d9da738a8bb6222bc0621fdef77589f0dda6d0f95f34aaa9281aa61a943ab
We call a number a mountain number if its middle digit is larger than any other digit. For example, 284 is a mountain number. How many 3-digit mountain numbers are there?
[ "240" ]
[ "We call a number a mountain number if its middle digit is larger than any other digit. For example, 284 is a mountain number. How many 3-digit mountain numbers are there?" ]
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-e0b043e0466f32ba5d193ba9027f1fc5014cd66342191f808cb6c9321f8d38bc
We call a number delicious if it has exactly 4 factors and is divisible by 2. How many numbers less than 99 are delicious?
[ "15" ]
[ "We call a number delicious if it has exactly 4 factors and is divisible by 2. How many numbers less than 99 are delicious?" ]
[ "aops_c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 7 }
23
0
0
omr-ws-56371ce4787c56d5c13ed0a322f00c35e0493ba65bb2dce9d9e3ca31512a8b0d
We call a pair \((a, b)\) of positive integers "friendly" if their difference is a perfect square of an integer. The numbers \(1, 2, 3, \ldots, n\) are colored with three distinct colors. It is known that there are two "friendly" positive integers with the same color. Find the least possible value of \(n\).
[ "14" ]
[ "We call a pair \\((a, b)\\) of positive integers \"friendly\" if their difference is a perfect square of an integer. The numbers \\(1, 2, 3, \\ldots, n\\) are colored with three distinct colors. It is known that there are two \"friendly\" positive integers with the same color. Find the least possible value of \\(n...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-32103b674a6ddfc6bc09db01139e23997b58d95fa6f085ff3e622bce6b511cf7
We call a pair of positive integers quare if their product is a perfect square. A subset $S$ of $\{1, 2, \ldots, 100\}$ is chosen, such that no two distinct elements of $S$ form a quare pair. Find the maximum possible number of elements in such a set $S$.
[ "61" ]
[ "We call a pair of positive integers quare if their product is a perfect square. A subset $S$ of $\\{1, 2, \\ldots, 100\\}$ is chosen, such that no two distinct elements of $S$ form a quare pair. Find the maximum possible number of elements in such a set $S$." ]
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-0f2b653f015b91af83806ace28544240413a6bf9d90b233016bb92f3d235c620
We call a permutation $(a_1, a_2, \cdots, a_n)$ of the set $\{1, 2, \cdots, n\}$ "good" if for any three natural numbers $i < j < k$, $n \nmid a_i + a_k - 2a_j$. Find all natural numbers $n \ge 3$ such that there exists a "good" permutation of the set $\{1, 2, \cdots, n\}$.
[ "\\( n = 2^k \\)" ]
[ "We call a permutation $(a_1, a_2, \\cdots, a_n)$ of the set $\\{1, 2, \\cdots, n\\}$ \"good\" if for any three natural numbers $i < j < k$, $n \\nmid a_i + a_k - 2a_j$. Find all natural numbers $n \\ge 3$ such that there exists a \"good\" permutation of the set $\\{1, 2, \\cdots, n\\}$." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 15, "genselect": 7, "tir": 21 }
43
0
0
omr-ws-bb27bcbc7976eb805f379195532d0da2a8157f140a10c1fe35e9744827858fe9
We call a positive integer alternative if its decimal digits are alternatively odd and even. Find all positive integers \(n\) such that \(n\) has an alternative multiple.
[ "\\text{All positive integers not divisible by }20" ]
[ "We call a positive integer alternative if its decimal digits are alternatively odd and even. Find all positive integers \\(n\\) such that \\(n\\) has an alternative multiple." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-329ad55a47e582da7985501520fe1891ad6815268a96771b9c871f525bf7fdcf
We call a positive integer basically prime if it is not divisible by a prime less than $15$. I pick all the integers from $1$ to $n$, and take the ratio of the number of basically prime integers to the number of integers that are not basically prime. As $n$ becomes large, to what number does this ratio approach?
[ "\\dfrac{192}{809}" ]
[ "We call a positive integer basically prime if it is not divisible by a prime less than $15$. I pick all the integers from $1$ to $n$, and take the ratio of the number of basically prime integers to the number of integers that are not basically prime. As $n$ becomes large, to what number does this ratio approach?" ...
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-7ce2b28160941a33a3d997059462ff21e948a0f104404cbf6d6649a64584ed29
We call a rectangle of size $2 \times 3$ (or $3 \times 2$) without one cell in a corner a $P$-rectangle. We call a rectangle of size $2 \times 3$ (or $3 \times 2$) without two cells in opposite corners a $S$-rectangle. Using some squares of size $2 \times 2$, some $P$-rectangles, and some $S$-rectangles, one forms a re...
[ "994000" ]
[ "We call a rectangle of size $2 \\times 3$ (or $3 \\times 2$) without one cell in a corner a $P$-rectangle. We call a rectangle of size $2 \\times 3$ (or $3 \\times 2$) without two cells in opposite corners a $S$-rectangle. Using some squares of size $2 \\times 2$, some $P$-rectangles, and some $S$-rectangles, one ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 1, "genselect": 1, "tir": 1 }
3
0
0
omr-ws-4b1c659cb215f504778a39d9ef57991fbe1e156166d9ba424763bfa785f4d75d
We call a rectangle of size \( 1 \times 2 \) a domino. A rectangle of size \( 2 \times 3 \) with two opposite corners removed (under the center of the rectangle) is called a tetramino. These figures can be rotated. Determine the minimal number of dominoes required to tile a rectangle of size \( 2008 \times 2010 \) usin...
[ "672680" ]
[ "We call a rectangle of size \\( 1 \\times 2 \\) a domino. A rectangle of size \\( 2 \\times 3 \\) with two opposite corners removed (under the center of the rectangle) is called a tetramino. These figures can be rotated. Determine the minimal number of dominoes required to tile a rectangle of size \\( 2008 \\times...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 11, "genselect": 4 }
15
0
0
omr-ws-097b16d273e112ec42748e02ae90d98529fa3d75c93c3cdd24b21e5fc086eb54
We call a sequence of \(n\) digits one or zero a code. A subsequence of a code is a palindrome if it is the same after we reverse the order of its digits. A palindrome is called nice if its digits occur consecutively in the code. a) What is the least number of palindromes in a code? b) What is the least number of nice ...
[ "n" ]
[ "We call a sequence of \\(n\\) digits one or zero a code. A subsequence of a code is a palindrome if it is the same after we reverse the order of its digits. A palindrome is called nice if its digits occur consecutively in the code.\na) What is the least number of palindromes in a code?\nb) What is the least number...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 7 }
7
0
0
omr-ws-248dd42b368af4007eb0acd80f681d968d3dd0b9890f38164a757637502ff1cd
We call a sequence of letters "red" if it consists only of the letters \(C, H, I, A\) (some of these letters may not appear in the sequence) and in which \(C\) is never immediately followed by \(H\), \(H\) is never immediately followed by \(I\), \(I\) is never immediately followed by \(A\), and \(A\) is never immediate...
[ "2916" ]
[ "We call a sequence of letters \"red\" if it consists only of the letters \\(C, H, I, A\\) (some of these letters may not appear in the sequence) and in which \\(C\\) is never immediately followed by \\(H\\), \\(H\\) is never immediately followed by \\(I\\), \\(I\\) is never immediately followed by \\(A\\), and \\(...
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-ecc93b8d7fdcf386e49a4817bda4264da2ced8f5b2e9c83173684e38e67020a1
We call a set of positive integers *good* if the greatest common divisor of all elements in the set is $1$. Let $a_n$ be the number of *good* subsets of $\{1, 2, \ldots, n\}$. Find all integers $n \ge 2019$ such that for all $0 < k < n$, $k \in \mathbb{Z}$, the inequality $\frac{a_{n+k}}{a_n} < \frac{a_n}{a_{n-k}}$ hol...
[ "all odd $n \\geq 2019$" ]
[ "We call a set of positive integers *good* if the greatest common divisor of all elements in the set is $1$. Let $a_n$ be the number of *good* subsets of $\\{1, 2, \\ldots, n\\}$. Find all integers $n \\ge 2019$ such that for all $0 < k < n$, $k \\in \\mathbb{Z}$, the inequality $\\frac{a_{n+k}}{a_n} < \\frac{a_n}{...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 1, "genselect": 1, "tir": 3 }
5
0
0
omr-ws-83c843d8297ee496fe90d64c2c587d6076f110f6e89fb38d8d9f772d2d42e225
We call a square table of a binary, if at each cell is written a single number 0 or 1. The binary table is called regular if each row and each column exactly have two units. Determine the number of regular size tables $n \times n$ ($n > 1$ - given a fixed positive integer). (We can assume that the rows and columns of t...
[ "\\frac{(n!)^2}{2^n} \\sum_{k=0}^n \\frac{(-1)^k (2n - 2k)!}{k! (n - k)! 2^{n - k}}" ]
[ "We call a square table of a binary, if at each cell is written a single number 0 or 1. The binary table is called regular if each row and each column exactly have two units. Determine the number of regular size tables $n \\times n$ ($n > 1$ - given a fixed positive integer). (We can assume that the rows and column...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 7, "genselect": 2 }
9
0
0
omr-ws-c304e16fb7d62d41614d2dbc0a24e962a2b75030b0e499bbcd06c7486acf5eed
We call an angle of a convex $n$-gon "good" if its sine is equal to the product of the sines of all other angles of the $n$-gon. What is the maximum number of good angles that an $n$-gon can have for each natural $n \ge 3$?
[ "1" ]
[ "We call an angle of a convex $n$-gon \"good\" if its sine is equal to the product of the sines of all other angles of the $n$-gon. What is the maximum number of good angles that an $n$-gon can have for each natural $n \\ge 3$?" ]
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-851187e8bff4e108068f350766cca4787ce19cf5c6e48fa4935ee0d2376c6f1b
We can conduct the following moves to a real number $x$: choose a positive integer $n$, and positive reals $a_1, a_2, \cdots, a_n$ whose reciprocals sum up to $1$. Let $x_0 = x$, and $x_k = \sqrt{x_{k-1} a_k}$ for all $1 \leq k \leq n$. Finally, let $y = x_n$. A number $M > 0$ is "tremendous" if for any $x \in \mathbb{...
[ "(4, \\infty)" ]
[ "We can conduct the following moves to a real number $x$: choose a positive integer $n$, and positive reals $a_1, a_2, \\cdots, a_n$ whose reciprocals sum up to $1$. Let $x_0 = x$, and $x_k = \\sqrt{x_{k-1} a_k}$ for all $1 \\leq k \\leq n$. Finally, let $y = x_n$. A number $M > 0$ is \"tremendous\" if for any $x \...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 8, "genselect": 6 }
14
0
0
omr-ws-778d7404de25e37d546fc2ce5e571d09c3cf68eefdf24e5b1d5c80a27aef4d0f
We can conduct the following moves to a real number \( x \): choose a positive integer \( n \), and positive reals \( a_1, a_2, \ldots, a_n \) whose reciprocals sum up to 1. Let \( x_0 = x \), and \( x_k = \sqrt{x_{k-1} a_k} \) for all \( 1 \leq k \leq n \). Finally, let \( y = x_n \). A number \( M > 0 \) is called "t...
[ "\\( M \\geq 4 \\)" ]
[ "We can conduct the following moves to a real number \\( x \\): choose a positive integer \\( n \\), and positive reals \\( a_1, a_2, \\ldots, a_n \\) whose reciprocals sum up to 1. Let \\( x_0 = x \\), and \\( x_k = \\sqrt{x_{k-1} a_k} \\) for all \\( 1 \\leq k \\leq n \\). Finally, let \\( y = x_n \\). A number \...
[ "aops_c6_high_school_olympiads" ]
[ "tir" ]
{ "tir": 7 }
7
0
0
omr-ws-6328e67fab7092c722aa111a9b0e3b9e96c059497644c3511e8fa25ccaee812a
We can label the squares of an $8 \times 8$ chess board from $1$ to $64$ in $64!$ different ways. For each way, we find $D$, the largest difference between the labels of two squares which are adjacent (orthogonally or diagonally). What is the smallest possible value of $D$?
[ "9" ]
[ "We can label the squares of an $8 \\times 8$ chess board from $1$ to $64$ in $64!$ different ways. For each way, we find $D$, the largest difference between the labels of two squares which are adjacent (orthogonally or diagonally). What is the smallest possible value of $D$?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 14, "genselect": 7 }
21
0
0
omr-ws-d460c31aa2afb5c0649c055e0d95a51e7582584276687a71d2c8c6056dd2ae8a
We can write $(x + 35)^n = \sum_{i=0}^n c_i x^i$ for some positive integer $n$ and real numbers $c_i$. If $c_0 = c_2$, what is $n$?
[ "50" ]
[ "We can write $(x + 35)^n = \\sum_{i=0}^n c_i x^i$ for some positive integer $n$ and real numbers $c_i$. If $c_0 = c_2$, what is $n$?" ]
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-22eaa043a641080c57c59fb470e39b3e6e79b343be496f944242725441e89b38
We can write $\sqrt{20 + 2\sqrt{91}} + \sqrt{20 - 2\sqrt{91}}$ in the form $x + \sqrt{y}$, where $x$ and $y$ are integers. Determine $x + y$.
[ "52" ]
[ "We can write $\\sqrt{20 + 2\\sqrt{91}} + \\sqrt{20 - 2\\sqrt{91}}$ in the form $x + \\sqrt{y}$, where $x$ and $y$ are integers. Determine $x + y$." ]
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-f49a41158f6c3e75a0b59308f1ba45bdfe18cd52da80833a1386deb178b4e9fb
We can write \[\sum_{k = 1}^{100} (-1)^k \cdot \frac{k^2 + k + 1}{k!} = \frac{a}{b!} - c,\]where $a,$ $b,$ and $c$ are positive integers. Find the smallest possible value of $a + b + c.$
[ "202" ]
[ "We can write\n\\[\\sum_{k = 1}^{100} (-1)^k \\cdot \\frac{k^2 + k + 1}{k!} = \\frac{a}{b!} - c,\\]where $a,$ $b,$ and $c$ are positive integers. Find the smallest possible value of $a + b + c.$" ]
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-129067c1a313a6212a5f24491ffde23f82b2785242577125cb3e3ae77f3e21a2
We choose 100 points in the coordinate plane. Let $N$ be the number of triples $(A,B,C)$ of distinct chosen points such that $A$ and $B$ have the same $y$-coordinate, and $B$ and $C$ have the same $x$-coordinate. Find the greatest value that $N$ can attain considering all possible ways to choose the points.
[ "8100" ]
[ "We choose 100 points in the coordinate plane. Let $N$ be the number of triples $(A,B,C)$ of distinct chosen points such that $A$ and $B$ have the same $y$-coordinate, and $B$ and $C$ have the same $x$-coordinate. Find the greatest value that $N$ can attain considering all possible ways to choose the points." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 1 }
17
0
0
omr-ws-384530ad9461226afd8807a8cf5a3b0b61e38677115297ce5eaaec8297bcb5bc
We choose \( n > 3 \) points on a circle and number them \( 1 \) to \( n \) in some order. We say that two non-adjacent points \( A \) and \( B \) are related if, in one of the arcs \( AB \), all the points are marked with numbers less than those at \( A \) and \( B \). If \( n = 10 \), calculate the sum of all possibl...
[ "" ]
[ "We choose \\( n > 3 \\) points on a circle and number them \\( 1 \\) to \\( n \\) in some order. We say that two non-adjacent points \\( A \\) and \\( B \\) are related if, in one of the arcs \\( AB \\), all the points are marked with numbers less than those at \\( A \\) and \\( B \\). If \\( n = 10 \\), calculate...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
1
omr-ws-ef745127867d984afcff50519f2646c80c76d512fc46c8b0d7b4da1f610633c7
We choose \( n \) numbers from \(-1, 1, 0\) and write them in a line such that their sum is 0. If the number of \(-1\)s is odd, the line is considered "bad"; if it is even, the line is considered "good". How many different good and bad lines can we get?
[ "\\frac{1}{2} \\left(3^{n} - (-1)^{n} \\right)" ]
[ "We choose \\( n \\) numbers from \\(-1, 1, 0\\) and write them in a line such that their sum is 0. If the number of \\(-1\\)s is odd, the line is considered \"bad\"; if it is even, the line is considered \"good\". How many different good and bad lines can we get?" ]
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-3aff01789c66922fd739c54e3dbd440c273a3bd7b28cad160cc20136da5b45c2
We choose \( n+1 \) points \( x_0 = 0, x_1, x_2, \ldots, x_n = 1 \) in the interval \([0,1]\). Assume the sequence of the distances between these points such that each distance occurs at least twice, except for the distance 1. Let \( S \) be the set of all distinct distances between these points. Calculate the sum of a...
[ "3" ]
[ "We choose \\( n+1 \\) points \\( x_0 = 0, x_1, x_2, \\ldots, x_n = 1 \\) in the interval \\([0,1]\\). Assume the sequence of the distances between these points such that each distance occurs at least twice, except for the distance 1. Let \\( S \\) be the set of all distinct distances between these points. Calculat...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-1ab0b97cc738408b642d7fa2736a799d0a840701c39c653940ea8fe0071985dd
We choose a subset $S$ from the set $A = \{1, 2, 3, \ldots, 1001\}$ with the condition that for any two elements $x$ and $y$ in $S$, their sum $x + y$ is not in $S$. What is the largest possible size of the set $S$?
[ "501" ]
[ "We choose a subset $S$ from the set $A = \\{1, 2, 3, \\ldots, 1001\\}$ with the condition that for any two elements $x$ and $y$ in $S$, their sum $x + y$ is not in $S$. What is the largest possible size of the set $S$?" ]
[ "aops_c4_high_school_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-4f7cff043ad0786f5edeb557c9fee568de76677ce525346b998ec5631a557931
We choose randomly $k$ positive natural numbers, $X_{1}, X_{2}, \ldots, X_{k}$, which are independent and identically distributed (iid) with $P(X_{i}=n)=2^{-n}$. Let $N$ be the number of non-chosen numbers in the set $\{1, 2, 3, \ldots, \max\{X_{i}\}\}$. Find the distribution of $N$.
[ "P(N = m) = \\frac{1}{2^{m+1}} \\text{ for } m \\geq 0" ]
[ "We choose randomly $k$ positive natural numbers, $X_{1}, X_{2}, \\ldots, X_{k}$, which are independent and identically distributed (iid) with $P(X_{i}=n)=2^{-n}$. Let $N$ be the number of non-chosen numbers in the set $\\{1, 2, 3, \\ldots, \\max\\{X_{i}\\}\\}$. Find the distribution of $N$." ]
[ "aops_c7_college_math" ]
[ "cot" ]
{ "cot": 8 }
8
0
0
omr-ws-3a5a41be51129b6923465ba6fb258c603748a2c85d364a8b900b18c7b597b0ab
We color each number in the set \( S = \{1, 2, \ldots, 61\} \) with one of 25 given colors, where it is not necessary that every color gets used. Let \( m \) be the number of non-empty subsets of \( S \) such that every number in the subset has the same color. What is the minimum possible value of \( m \)?
[ "119" ]
[ "We color each number in the set \\( S = \\{1, 2, \\ldots, 61\\} \\) with one of 25 given colors, where it is not necessary that every color gets used. Let \\( m \\) be the number of non-empty subsets of \\( S \\) such that every number in the subset has the same color. What is the minimum possible value of \\( m \...
[ "aops_c6_high_school_olympiads", "c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 2 }
18
0
0
omr-ws-1832c2e944a1eed02318f7c26349eab81d8d32caf96b4d425b8c4128b0fe8d13
We color each unit of an $8 \times 8$ table either green or blue such that there are $a$ green unit squares in each $3 \times 3$ square and $b$ blue unit squares in each $2 \times 4$ rectangle. Find all possible values of $(a, b)$.
[ "(0, 8)" ]
[ "We color each unit of an $8 \\times 8$ table either green or blue such that there are $a$ green unit squares in each $3 \\times 3$ square and $b$ blue unit squares in each $2 \\times 4$ rectangle. Find all possible values of $(a, b)$." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 11 }
11
0
0
omr-ws-32c8ae86681390644a12fe52fd174c0f482d58f2f4a49bb0c8e2b14fe1df8995
We color one of the numbers $1, \ldots, 8$ with white or black according to the following rules: i) Number $4$ gets colored white and at least one of the following numbers gets colored black. ii) If two numbers $a, b$ are colored in different colors and $a + b \leq 8$, then number $a + b$ gets colored black. iii) If tw...
[ "BBBWBBBW, BWBWBWBW, BWBWBWBB" ]
[ "We color one of the numbers $1, \\ldots, 8$ with white or black according to the following rules:\ni) Number $4$ gets colored white and at least one of the following numbers gets colored black.\nii) If two numbers $a, b$ are colored in different colors and $a + b \\leq 8$, then number $a + b$ gets colored black.\n...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 12, "genselect": 6, "tir": 7 }
25
0
0
omr-ws-f4828fd428b6a9d2d343e6c2f42ebaa47bf7be04ad4cb81e5e0a91d7206d0655
We color some unit squares in a $99 \times 99$ square grid with one of 5 given distinct colors, such that each color appears the same number of times. On each row and on each column, there are no differently colored unit squares. Find the maximum possible number of colored unit squares.
[ "1900" ]
[ "We color some unit squares in a $99 \\times 99$ square grid with one of 5 given distinct colors, such that each color appears the same number of times. On each row and on each column, there are no differently colored unit squares. Find the maximum possible number of colored unit squares." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 37, "genselect": 8, "tir": 6 }
51
0
0
omr-ws-69aa2a706e06b685f4de6c19ee50593a4fe111e406330fe3890140051872f95f
We color some unit squares in a $99 \times 99$ square grid with one of five given distinct colors such that each color appears the same number of times. On each row and on each column, there are no differently colored unit squares. Find the maximum possible number of colored unit squares and give an example in this cas...
[ "1900" ]
[ "We color some unit squares in a $99 \\times 99$ square grid with one of five given distinct colors such that each color appears the same number of times. On each row and on each column, there are no differently colored unit squares. Find the maximum possible number of colored unit squares and give an example in th...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 10, "genselect": 8 }
18
0
0
omr-ws-e7951534cefc622da43634c842b15860f8b8c00786ada9b4fd033547909a2f75
We color the cells of an $n \times n$ board either red or blue. A red queen can move in any direction but only between red cells, and a blue queen can move in any direction but only between blue cells. Two queens attack each other if one can move to the other's position in a single move. Find the greatest integer $k$ s...
[ "\\( k = \\frac{n^2}{2} \\) for even \\( n \\) and \\( k = \\frac{n(n+1)}{2} \\) for odd \\( n \\)" ]
[ "We color the cells of an $n \\times n$ board either red or blue. A red queen can move in any direction but only between red cells, and a blue queen can move in any direction but only between blue cells. Two queens attack each other if one can move to the other's position in a single move. Find the greatest integer...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-852cb00ac7874d9af0e5b0f55cb376e9d4d1a063275240682fb864be07049a07
We color the numbers $2, 3, 4, \ldots, 1024$ with $k$ different colors such that if $a$ is a multiple of $b$, then $a$ and $b$ have different colors. Find the minimum value of $k$.
[ "10" ]
[ "We color the numbers $2, 3, 4, \\ldots, 1024$ with $k$ different colors such that if $a$ is a multiple of $b$, then $a$ and $b$ have different colors. Find the minimum value of $k$." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-d4bd1ae487dbebd68dd3d94a38a3dc0e1c6461494225a8fde5c67d7da217708f
We color the numbers from $1$ to $n$ with three distinct colors: white, black, and red, such that each color appears more than $n/4$ times. Let $S$ be the set of all triples $(a, b, c)$ where $a, b, c$ are distinct numbers from $1$ to $n$, $a + b = c$, and $a, b, c$ are of different colors. Calculate the minimum possib...
[ "351" ]
[ "We color the numbers from $1$ to $n$ with three distinct colors: white, black, and red, such that each color appears more than $n/4$ times. Let $S$ be the set of all triples $(a, b, c)$ where $a, b, c$ are distinct numbers from $1$ to $n$, $a + b = c$, and $a, b, c$ are of different colors. Calculate the minimum p...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 5, "genselect": 3 }
8
0
0
omr-ws-7f1e2fdb7f7187ddd23cc30e6ed28aea5de0b148d96ee9d42e8c2dd147c33d71
We color the vertices of a regular polygon with $n$ sides using two colors. A diagonal is considered good if it connects two vertices colored with different colors. A coloring is perfect if it is possible to divide the polygon internally into triangles by tracing only good diagonals, with no two diagonals sharing any p...
[ "2" ]
[ "We color the vertices of a regular polygon with $n$ sides using two colors. A diagonal is considered good if it connects two vertices colored with different colors. A coloring is perfect if it is possible to divide the polygon internally into triangles by tracing only good diagonals, with no two diagonals sharing ...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 9 }
9
0
0
omr-ws-206f96e72cf7bf6efd6d6b064f7aacbca38c5b5ca3f1a8416e7fac2431f21dcf
We colour $8N^3$ lattice points red. On each red point $P$, we write the total number of red points on the vertical and horizontal lines through $P$. Let $M(N)$ be the smallest number that is written at least $N+1$ times. Calculate $M(3)$.
[ "12" ]
[ "We colour $8N^3$ lattice points red. On each red point $P$, we write the total number of red points on the vertical and horizontal lines through $P$. Let $M(N)$ be the smallest number that is written at least $N+1$ times. Calculate $M(3)$." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 1, "genselect": 3 }
4
0
0
omr-ws-52491da4b13cd5f44a04b8f759511461ffe3cc6a5e6d4df082257fdf5e505cb5
We colour every square of a $2009 \times 2009$ board with one of $n$ colours. A colour is called connected if either there is only one square of that colour or any two squares of the same colour can be reached from one another by a sequence of moves of a chess queen without intermediate stops at squares of another colo...
[ "2" ]
[ "We colour every square of a $2009 \\times 2009$ board with one of $n$ colours. A colour is called connected if either there is only one square of that colour or any two squares of the same colour can be reached from one another by a sequence of moves of a chess queen without intermediate stops at squares of anothe...
[ "aops_c6_high_school_olympiads" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-859a31c95c9bc3364a1564d2aed520837416a97bbf5ac4d556cac8ae5e6ae8d1
We consider $5 \times 5$ tables containing a real number in each of the 25 cells. The same number may occur in different cells, but no row or column contains five equal numbers. Such a table is balanced if the number in the middle cell of every row and column is the average of the numbers in that row or column. A cell ...
[ "8" ]
[ "We consider $5 \\times 5$ tables containing a real number in each of the 25 cells. The same number may occur in different cells, but no row or column contains five equal numbers. Such a table is balanced if the number in the middle cell of every row and column is the average of the numbers in that row or column. A...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 6, "genselect": 1 }
7
0
0
omr-ws-10aa76847520867f479666e6e058ef7905ad38c5b730d1bb37e11c5c84358e0e
We consider a square of side $8$. By joining the midpoints of each pair of adjacent sides, we get a second square, and if we continue like this, joining the midpoints of the adjacent sides of each drawn square, we obtain a new square. What is the area of the sixth square obtained?
[ "1" ]
[ "We consider a square of side $8$. By joining the midpoints of each pair of adjacent sides, we get a second square, and if we continue like this, joining the midpoints of the adjacent sides of each drawn square, we obtain a new square. What is the area of the sixth square obtained?" ]
[ "aops_c4_high_school_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-e5f3a16ec954b071fa77950e32d70ed82a15a09c5748918d159a07d3cda6065b
We consider all possible pairs of 10-gons \( A \) and \( B \) (possibly non-convex) in the plane. The contour of polygon \( B \) divides polygon \( A \) into \( k \) parts. Find the largest possible value of \( k \).
[ "51" ]
[ "We consider all possible pairs of 10-gons \\( A \\) and \\( B \\) (possibly non-convex) in the plane. The contour of polygon \\( B \\) divides polygon \\( A \\) into \\( k \\) parts. Find the largest possible value of \\( k \\)." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 13, "genselect": 5 }
18
0
0
omr-ws-bea3d21d0dde00a243153d44e8ce17cd2125d570f9ea78b61b88e42977e01b7a
We consider maps on two spheres, say the earth and the moon. Each region on the earth is a country, and has a corresponding region or colony on the moon. We desire to color the countries and colonies so that: 1) Each country receives the same color as its colony, and 2) If two countries or colonies share a common borde...
[ "8" ]
[ "We consider maps on two spheres, say the earth and the moon. Each region on the earth is a country, and has a corresponding region or colony on the moon. We desire to color the countries and colonies so that:\n1) Each country receives the same color as its colony, and\n2) If two countries or colonies share a commo...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 7, "genselect": 6 }
13
0
0
omr-ws-cc41702bb454ff275d5380a1251463fe16af8282b89e9d7c9ef8aa4a95f0b714
We consider security codes consisting of four digits. We say that one code dominates another code if each digit of the first code is at least as large as the corresponding digit in the second code. For example, 4961 dominates 0761, because 4 ≥ 0, 9 ≥ 7, 6 ≥ 6, and 1 ≥ 1. We would like to assign a colour to each securit...
[ "37" ]
[ "We consider security codes consisting of four digits. We say that one code dominates another code if each digit of the first code is at least as large as the corresponding digit in the second code. For example, 4961 dominates 0761, because 4 ≥ 0, 9 ≥ 7, 6 ≥ 6, and 1 ≥ 1. We would like to assign a colour to each se...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 47 }
47
0
0
omr-ws-dff0b214d104f306ed810370ec9670b903123fdc72c2e222610d342f84d12aeb
We construct a base 2 number by flipping a coin repeatedly. If we get tails, we write a $0$ and stop. If we get heads, we write a $1$ and continue flipping. Each subsequent flip follows the same rule. What is the expected base 10 value of the constructed number?
[ "\\(\\frac{4}{3}\\)" ]
[ "We construct a base 2 number by flipping a coin repeatedly. If we get tails, we write a $0$ and stop. If we get heads, we write a $1$ and continue flipping. Each subsequent flip follows the same rule. What is the expected base 10 value of the constructed number?" ]
[ "aops_c4_high_school_math" ]
[ "additional_problems" ]
{ "additional_problems": 1 }
1
0
0
omr-ws-4d50bcfbdeba8a1ee715c71a1b73cfb242c950fbc2bd2baf47a2d23d61448091
We construct a solid figure through the following process: 1. Start with a solid clay cube of side length 8. 2. Remove all clay within a smaller cube formed by connecting the centers of each face of the solid cube. 3. Add back the clay in the shape of an even smaller cube, formed by connecting the centers of the faces ...
[ "\\dfrac{512(2\\sqrt{2} - 1)}{7}" ]
[ "We construct a solid figure through the following process:\n1. Start with a solid clay cube of side length 8.\n2. Remove all clay within a smaller cube formed by connecting the centers of each face of the solid cube.\n3. Add back the clay in the shape of an even smaller cube, formed by connecting the centers of th...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 8, "genselect": 4 }
12
0
0
omr-ws-c0e6fd55ba6002dee587645046b1a68120157af9d030b8cbad3824e4f06b6dde
We construct right triangles $ABC, BDC, DEC, EZC$ with $\widehat{A} = \widehat{CBD} = \widehat{CDE} = \widehat{CEZ} = 90^\circ$. Given $CA=25$, $AB=36$, $BD=9$, $DE=4$, $EZ=1$, and $ZC=x$, find the area of the square with side length $x$.
[ "2019" ]
[ "We construct right triangles $ABC, BDC, DEC, EZC$ with $\\widehat{A} = \\widehat{CBD} = \\widehat{CDE} = \\widehat{CEZ} = 90^\\circ$. Given $CA=25$, $AB=36$, $BD=9$, $DE=4$, $EZ=1$, and $ZC=x$, find the area of the square with side length $x$." ]
[ "aops_c4_high_school_math" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 18 }
34
0
0
omr-ws-298ebeb6c31db03bc1e613b51025ccf8a8be52fc173b9c658f13e9c27c6bf91b
We construct the Determinant-1 Triangle as follows: - In the \( n \)th row, the first and last entries equal 1. - Let \( d \) be an entry of the \( n \)th row other than a first or last entry. Let \( b \) and \( c \) be the two entries in the previous row directly above \( d \) and let \( a \) be the entry that is dire...
[ "50" ]
[ "We construct the Determinant-1 Triangle as follows:\n- In the \\( n \\)th row, the first and last entries equal 1.\n- Let \\( d \\) be an entry of the \\( n \\)th row other than a first or last entry. Let \\( b \\) and \\( c \\) be the two entries in the previous row directly above \\( d \\) and let \\( a \\) be t...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 6, "genselect": 1 }
7
0
0
omr-ws-1abbe0f7f6c2f3b185a1f292e8d4a0512101eef6d9440feb0e718d2ed1ea29e9
We continuously sample from the uniform distribution U(0,1) until the sum of the samples exceeds 1. What is the expected number of samples needed?
[ "e" ]
[ "We continuously sample from the uniform distribution U(0,1) until the sum of the samples exceeds 1. What is the expected number of samples needed?" ]
[ "aops_c7_college_math" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-3f66df63c4b645560d56c7be5ec8ea69b7897943757aaccb67f1b784710da44f
We deal $n-1$ cards in some way to $n$ people sitting around a table. From then on, in one move a person with at least $2$ cards gives one card to each of his/her neighbors. Let $T(n)$ be the maximum number of moves required to reach a state where everyone has at most one card. Find $T(10)$.
[ "20" ]
[ "We deal $n-1$ cards in some way to $n$ people sitting around a table. From then on, in one move a person with at least $2$ cards gives one card to each of his/her neighbors. Let $T(n)$ be the maximum number of moves required to reach a state where everyone has at most one card. Find $T(10)$." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 2, "genselect": 6 }
8
0
0
omr-ws-95d841d8903af4054e5896f3927239ceee7cdf30ff0ddcd8e83d385f7d456d20
We define a beehive of order $n$ as follows: a beehive of order 1 is one hexagon. To construct a beehive of order $n$, take a beehive of order $n-1$ and draw a layer of hexagons in the exterior of these hexagons. Initially, some hexagons are infected by a virus. If a hexagon has been infected, it will always be infecte...
[ "\\( f(n) = 3n^2 - 3n - \\left\\lfloor \\frac{3}{2}(n-1)^2 \\right\\rfloor = 3n^2 - \\left\\lfloor \\frac{3}{2}n^2 + \\frac{3}{2} \\right\\rfloor \\)" ]
[ "We define a beehive of order $n$ as follows: a beehive of order 1 is one hexagon. To construct a beehive of order $n$, take a beehive of order $n-1$ and draw a layer of hexagons in the exterior of these hexagons. Initially, some hexagons are infected by a virus. If a hexagon has been infected, it will always be in...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect", "tir" ]
{ "cot": 5, "genselect": 8, "tir": 6 }
19
0
0
omr-ws-9b8635aeaf20f24bced7d0c44b6eeaf5dbaccf829f6496f627dd8b11dece76d9
We define a function $f(x)$ such that $f(11)=34$, and if there exists an integer $a$ such that $f(a)=b$, then $f(b)$ is defined and $f(b)=3b+1$ if $b$ is odd $f(b)=\frac{b}{2}$ if $b$ is even. What is the smallest possible number of integers in the domain of $f$?
[ "15" ]
[ "We define a function $f(x)$ such that $f(11)=34$, and if there exists an integer $a$ such that $f(a)=b$, then $f(b)$ is defined and\n\n$f(b)=3b+1$ if $b$ is odd\n\n$f(b)=\\frac{b}{2}$ if $b$ is even.\n\nWhat is the smallest possible number of integers in the domain of $f$?" ]
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-ff46e9411f5ec97df018920c8cc213ae33458964079488a511722680ef17514f
We define a sequence \( x_1 = \sqrt{3}, x_2 = -1, x_3 = 2 - \sqrt{3} \), and for all \( n \geq 4 \), \[ (x_n + x_{n-3})(1 - x^2_{n-1}x^2_{n-2}) = 2x_{n-1}(1 + x^2_{n-2}). \] Suppose \( m \) is the smallest positive integer for which \( x_m \) is undefined. Compute \( m \).
[ "10" ]
[ "We define a sequence \\( x_1 = \\sqrt{3}, x_2 = -1, x_3 = 2 - \\sqrt{3} \\), and for all \\( n \\geq 4 \\),\n\\[\n(x_n + x_{n-3})(1 - x^2_{n-1}x^2_{n-2}) = 2x_{n-1}(1 + x^2_{n-2}).\n\\]\nSuppose \\( m \\) is the smallest positive integer for which \\( x_m \\) is undefined. Compute \\( m \\)." ]
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 12, "genselect": 8 }
20
0
0
omr-ws-1b09b3a4cab28586a656be9f5dcf8e6d40c38ab3b0a9bb47ce114cb1e72c78c1
We define a sequence of natural numbers by the initial values \(a_0 = a_1 = a_2 = 1\) and the recursion \[ a_n = \left\lfloor \frac{n}{a_{n-1}a_{n-2}a_{n-3}} \right\rfloor \] for all \(n \ge 3\). Find the value of \(a_{2022}\).
[ "674" ]
[ "We define a sequence of natural numbers by the initial values \\(a_0 = a_1 = a_2 = 1\\) and the recursion \n\\[ a_n = \\left\\lfloor \\frac{n}{a_{n-1}a_{n-2}a_{n-3}} \\right\\rfloor \\]\nfor all \\(n \\ge 3\\). Find the value of \\(a_{2022}\\)." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 19 }
35
0
0
omr-ws-9c81e031bd794a5cc2911091f46b49d38d307584ebbd8487f4032c7281f25024
We define a sequence of numbers \(a_n\) such that \(a_0 = 1\) and for all \(n \geq 0\): \[2a_{n+1}^3 + 2a_n^3 = 3a_{n+1}^2 a_n + 3a_{n+1} a_n^2.\] Find the sum of all possible values of \(a_{2023}\).
[ "\\(\\frac{2^{2024} + 2^{-2023}}{3}\\)" ]
[ "We define a sequence of numbers \\(a_n\\) such that \\(a_0 = 1\\) and for all \\(n \\geq 0\\):\n\\[2a_{n+1}^3 + 2a_n^3 = 3a_{n+1}^2 a_n + 3a_{n+1} a_n^2.\\]\nFind the sum of all possible values of \\(a_{2023}\\)." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 9, "tir": 1 }
10
0
0
omr-ws-472ba1faff298f0d4d60d8e0a79254eeeb1f3b0c1aafcb34ce96472fdf15b44c
We define the function \( f \) as follows: \[ f(x) = \begin{cases} \frac{x}{2} & \text{if } x \text{ is even} \\ x-1 & \text{if } x \text{ is odd} \end{cases} \] The path of \( x \), denoted as \( \text{path}(x) \), is defined such that: 1. \( x \in \text{path}(x) \) 2. If \( y \in \text{path}(x) \), then \( f(y) \in \...
[ "a" ]
[ "We define the function \\( f \\) as follows:\n\\[ f(x) = \\begin{cases}\n\\frac{x}{2} & \\text{if } x \\text{ is even} \\\\\nx-1 & \\text{if } x \\text{ is odd}\n\\end{cases} \\]\n\nThe path of \\( x \\), denoted as \\( \\text{path}(x) \\), is defined such that:\n1. \\( x \\in \\text{path}(x) \\)\n2. If \\( y \\in...
[ "aops_c4_high_school_math" ]
[ "cot", "genselect" ]
{ "cot": 2, "genselect": 7 }
9
0
0
omr-ws-c7f83e151f5794412a8d3ff83251b40ae30c815fa56af7ce1530bbe92f953c7a
We define the sets \( A_1, A_2, \ldots, A_{160} \) such that \( |A_i| = i \) for all \( i = 1, 2, \ldots, 160 \). By removing the same number of elements from each of these sets in each step, we create new sets \( M_1, M_2, \ldots, M_n \). Find the minimum value of \( n \) such that all elements from \( A_1, A_2, \ldot...
[ "8" ]
[ "We define the sets \\( A_1, A_2, \\ldots, A_{160} \\) such that \\( |A_i| = i \\) for all \\( i = 1, 2, \\ldots, 160 \\). By removing the same number of elements from each of these sets in each step, we create new sets \\( M_1, M_2, \\ldots, M_n \\). Find the minimum value of \\( n \\) such that all elements from ...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 7, "tir": 1 }
8
0
0
omr-ws-3c77676612f8dc65815230e6d4e58d46290558776b35cb74e3f78aaa3ea8e84d
We define two sequences of vectors $(\mathbf{v}_n)$ and $(\mathbf{w}_n)$ as follows: First, $\mathbf{v}_0 = \begin{pmatrix} 1 \\ 3 \end{pmatrix},$ $\mathbf{w}_0 = \begin{pmatrix} 4 \\ 0 \end{pmatrix}.$ Then for all $n \ge 1,$ $\mathbf{v}_n$ is the projection of $\mathbf{w}_{n - 1}$ onto $\mathbf{v}_0,$ and $\mathbf{w}_...
[ "\\begin{pmatrix} 4/9 \\\\ 4/3 \\end{pmatrix}" ]
[ "We define two sequences of vectors $(\\mathbf{v}_n)$ and $(\\mathbf{w}_n)$ as follows: First, $\\mathbf{v}_0 = \\begin{pmatrix} 1 \\\\ 3 \\end{pmatrix},$ $\\mathbf{w}_0 = \\begin{pmatrix} 4 \\\\ 0 \\end{pmatrix}.$ Then for all $n \\ge 1,$ $\\mathbf{v}_n$ is the projection of $\\mathbf{w}_{n - 1}$ onto $\\mathbf{v...
[ "MATH_training_set" ]
[ "cot" ]
{ "cot": 16 }
16
0
0
omr-ws-3221bfcb89ec544767f99c21875610334539d566ef801d26680b04bf20221ee5
We denote with \(m_a\), \(m_g\) the arithmetic mean, respectively geometric mean, of the positive numbers \(x, y\). a) If \(m_a + m_g = y - x\), determine the value of \(\frac{x}{y}\). b) Prove that there exists exactly one pair of different positive integers \((x, y)\) for which \(m_a + m_g = 40\).
[ "(5, 45)" ]
[ "We denote with \\(m_a\\), \\(m_g\\) the arithmetic mean, respectively geometric mean, of the positive numbers \\(x, y\\).\n\na) If \\(m_a + m_g = y - x\\), determine the value of \\(\\frac{x}{y}\\).\n\nb) Prove that there exists exactly one pair of different positive integers \\((x, y)\\) for which \\(m_a + m_g = ...
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 13 }
13
0
0
omr-ws-18d0e7c77f1bf8429ca15431758a48886c790f8619d05ce19c4e3d6d2d7a48c8
We distribute 65 balls of different shapes and colors into two boxes. The colors of the balls are either white, yellow, red, or black. Suppose that when we choose 5 balls of the same size, we find at least two balls with the same color. Determine the minimum number of balls in one of the boxes that must have the same s...
[ "9" ]
[ "We distribute 65 balls of different shapes and colors into two boxes. The colors of the balls are either white, yellow, red, or black. Suppose that when we choose 5 balls of the same size, we find at least two balls with the same color. Determine the minimum number of balls in one of the boxes that must have the s...
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 4, "genselect": 3 }
7
0
0
omr-ws-f2efb4cc0a9e528559acffa935523685fe6f8512dad185dd8c38993c2acd065e
We divide 25 arbitrary numbers into \( k \) subsets such that: 1) Every subset contains 5 numbers; 2) Each pair of subsets shares at most 1 number. Find the maximum value of \( k \).
[ "30" ]
[ "We divide 25 arbitrary numbers into \\( k \\) subsets such that:\n1) Every subset contains 5 numbers;\n2) Each pair of subsets shares at most 1 number.\nFind the maximum value of \\( k \\)." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "tir" ]
{ "cot": 16, "tir": 1 }
17
0
0
omr-ws-a63d3d6c5a4d5493a2df39acff288788b4ca379c44cb530cdd04310fa02af428
We divide a square into $16^2$ smaller squares, all of the same size. Each smaller square is painted with a certain color, with the restriction that in each column and each row at most $4$ distinct colors appear. Determine the maximum number of colors that can be used.
[ "16" ]
[ "We divide a square into $16^2$ smaller squares, all of the same size. Each smaller square is painted with a certain color, with the restriction that in each column and each row at most $4$ distinct colors appear. Determine the maximum number of colors that can be used." ]
[ "aops_c6_high_school_olympiads" ]
[ "cot", "genselect" ]
{ "cot": 13, "genselect": 5 }
18
0
0
omr-ws-41a34fa91750e59ba72af41f08e0e0d30cd5786f1bb6d18b9645681b7be6bf39
We divide the entire \(\mathbb{Z}\) into \(n\) subsets such that the difference of any two elements in a subset will not be a prime number. \(n\) is at least?
[ "4" ]
[ "We divide the entire \\(\\mathbb{Z}\\) into \\(n\\) subsets such that the difference of any two elements in a subset will not be a prime number. \\(n\\) is at least?" ]
[ "aops_c6_high_school_olympiads" ]
[ "cot" ]
{ "cot": 15 }
15
0
0