sequence_id stringlengths 7 7 | sequence_name stringlengths 4 573 | sequence listlengths 1 348 | keywords listlengths 1 7 | score int64 1 2.47k | offset_a int64 -14,827 666,262,453B | offset_b int64 0 635M ⌀ | cross_references listlengths 1 128 ⌀ | former_ids listlengths 1 3 ⌀ | author stringlengths 7 231 ⌀ | timestamp timestamp[us]date 1999-12-11 03:00:00 2026-01-19 02:46:49 | filename stringlengths 29 29 | hash stringlengths 32 32 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
A000301 | a(n) = a(n-1)*a(n-2) with a(0) = 1, a(1) = 2; also a(n) = 2^Fibonacci(n). | [
"1",
"2",
"2",
"4",
"8",
"32",
"256",
"8192",
"2097152",
"17179869184",
"36028797018963968",
"618970019642690137449562112",
"22300745198530623141535718272648361505980416",
"13803492693581127574869511724554050904902217944340773110325048447598592"
] | [
"nonn",
"easy"
] | 99 | 0 | 2 | [
"A000045",
"A000079",
"A000301",
"A000304",
"A010098",
"A010099",
"A010100",
"A073115",
"A124091",
"A244003"
] | null | N. J. A. Sloane, Mar 15 1996 | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000301.seq | 510258cb8af60f3ef440311ce1ef3f4b |
A000302 | Powers of 4: a(n) = 4^n. | [
"1",
"4",
"16",
"64",
"256",
"1024",
"4096",
"16384",
"65536",
"262144",
"1048576",
"4194304",
"16777216",
"67108864",
"268435456",
"1073741824",
"4294967296",
"17179869184",
"68719476736",
"274877906944",
"1099511627776",
"4398046511104",
"17592186044416",
"70368744177... | [
"easy",
"nonn",
"nice",
"core"
] | 395 | 0 | 2 | [
"A000302",
"A000351",
"A024036",
"A032443",
"A052539",
"A083420",
"A249307"
] | [
"M3518",
"N1428"
] | N. J. A. Sloane | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000302.seq | 5166c5dc90334a13f5eee99007555393 |
A000303 | Number of permutations of [n] in which the longest increasing run has length 2. | [
"0",
"1",
"4",
"16",
"69",
"348",
"2016",
"13357",
"99376",
"822040",
"7477161",
"74207208",
"797771520",
"9236662345",
"114579019468",
"1516103040832",
"21314681315997",
"317288088082404",
"4985505271920096",
"82459612672301845",
"1432064398910663704",
"2605477146554050727... | [
"nonn"
] | 39 | 1 | 3 | [
"A000303",
"A000402",
"A000434",
"A000456",
"A000467",
"A001250",
"A001251",
"A001252",
"A001253",
"A008304",
"A010026",
"A049774",
"A211318",
"A230055"
] | [
"M3522",
"N1430"
] | N. J. A. Sloane | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000303.seq | ff1e726dee6711f78e86f69b7ea3b25c |
A000304 | a(n) = a(n-1)*a(n-2). | [
"2",
"3",
"6",
"18",
"108",
"1944",
"209952",
"408146688",
"85691213438976",
"34974584955819144511488",
"2997014624388697307377363936018956288",
"104819342594514896999066634490728502944926883876041385836544"
] | [
"nonn"
] | 57 | 2 | 1 | [
"A000045",
"A000301",
"A000304",
"A001222",
"A006519",
"A010098",
"A038500",
"A249406"
] | null | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000304.seq | 531efb5f2f03431e21996050e5a498d5 |
A000305 | Number of certain rooted planar maps. | [
"1",
"4",
"18",
"89",
"466",
"2537",
"14209",
"81316",
"473338",
"2793454",
"16674417",
"100487896",
"610549829",
"3735850007",
"23000055178",
"142370597601",
"885521350882",
"5531501612071",
"34686798239678",
"218273864005214",
"1377897874711437"
] | [
"nonn"
] | 32 | 1 | 2 | [
"A000305",
"A046652"
] | [
"M3543",
"N1435"
] | N. J. A. Sloane | 2025-12-20T04:22:21 | oeisdata/seq/A000/A000305.seq | a62720d54db54db8e882ad31e5cac64b |
A000306 | Number of trees of diameter 8. | [
"1",
"4",
"19",
"66",
"219",
"645",
"1813",
"4802",
"12265",
"30198",
"72396",
"169231",
"387707",
"871989",
"1930868",
"4215615",
"9091410",
"19389327",
"40944999",
"85691893",
"177898521",
"366614456",
"750494796",
"1526979694",
"3089556090",
"6219191608",
"1246... | [
"nonn"
] | 39 | 9 | 2 | [
"A000306",
"A034853"
] | [
"M3552",
"N1440"
] | N. J. A. Sloane | 2023-05-19T04:23:04 | oeisdata/seq/A000/A000306.seq | 36da5916ec187dccf5805382ab7cad03 |
A000307 | Number of 4-level labeled rooted trees with n leaves. | [
"1",
"1",
"4",
"22",
"154",
"1304",
"12915",
"146115",
"1855570",
"26097835",
"402215465",
"6734414075",
"121629173423",
"2355470737637",
"48664218965021",
"1067895971109199",
"24795678053493443",
"607144847919796830",
"15630954703539323090",
"421990078975569031642",
"1191809... | [
"nonn",
"easy"
] | 73 | 0 | 3 | [
"A000110",
"A000258",
"A000307",
"A000357",
"A000405",
"A001669",
"A039810",
"A039811",
"A039812",
"A144150"
] | [
"M3590",
"N1455"
] | N. J. A. Sloane | 2026-01-03T02:49:50 | oeisdata/seq/A000/A000307.seq | 151d358723fad86445de6f5c914f50a3 |
A000308 | a(n) = a(n-1)*a(n-2)*a(n-3) with a(1)=1, a(2)=2 and a(3)=3. | [
"1",
"2",
"3",
"6",
"36",
"648",
"139968",
"3265173504",
"296148833645101056",
"135345882205792807436868315512832",
"130876399105969522361889021452224949874232743897657526714368"
] | [
"nonn"
] | 19 | 1 | 2 | [
"A000304",
"A000308",
"A000336",
"A063401"
] | null | N. J. A. Sloane | 2022-02-01T00:52:27 | oeisdata/seq/A000/A000308.seq | e523cea881b64f0d0f1948c6aed48e9f |
A000309 | Number of rooted planar bridgeless cubic maps with 2n nodes. | [
"1",
"1",
"4",
"24",
"176",
"1456",
"13056",
"124032",
"1230592",
"12629760",
"133186560",
"1436098560",
"15774990336",
"176028860416",
"1990947110912",
"22783499599872",
"263411369705472",
"3073132646563840",
"36143187370967040",
"428157758086840320",
"5105072641718353920",
... | [
"nonn",
"nice"
] | 115 | 0 | 3 | [
"A000139",
"A000168",
"A000260",
"A000264",
"A000309",
"A000356",
"A000698",
"A000699",
"A002005",
"A006335",
"A062980",
"A267827",
"A358091"
] | [
"M3601",
"N1460"
] | N. J. A. Sloane and Robert G. Wilson v | 2025-09-22T16:00:13 | oeisdata/seq/A000/A000309.seq | 494b2ae14a9c1893ed0f7bfe2ee37379 |
A000310 | Coefficients of iterated exponentials. | [
"1",
"4",
"26",
"234",
"2696",
"37919",
"630521",
"12111114",
"264051201",
"6445170229",
"174183891471",
"5164718385337",
"166737090160871",
"5822980248613990",
"218756388226681557",
"8797723991458469015",
"377159237609540937788",
"17170729962232112834302",
"827382365085791968518... | [
"nonn"
] | 37 | 1 | 2 | [
"A000268",
"A000310",
"A000359",
"A000406",
"A001765",
"A003713",
"A039816"
] | [
"M3612",
"N1464"
] | N. J. A. Sloane | 2022-02-12T03:38:06 | oeisdata/seq/A000/A000310.seq | a978f7e8521cbbf5799fc2def51a3636 |
A000311 | Schroeder's fourth problem; also series-reduced rooted trees with n labeled leaves; also number of total partitions of n. | [
"0",
"1",
"1",
"4",
"26",
"236",
"2752",
"39208",
"660032",
"12818912",
"282137824",
"6939897856",
"188666182784",
"5617349020544",
"181790703209728",
"6353726042486272",
"238513970965257728",
"9571020586419012608",
"408837905660444010496",
"18522305410364986906624"
] | [
"nonn",
"core",
"easy",
"nice"
] | 294 | 0 | 4 | [
"A000084",
"A000110",
"A000169",
"A000311",
"A000669",
"A000670",
"A001003",
"A001678",
"A002846",
"A005121",
"A005640",
"A005804",
"A005805",
"A006351",
"A007827",
"A042977",
"A048816",
"A060356",
"A064060",
"A119649",
"A133314",
"A134685",
"A134991",
"A135494",
"A14... | [
"M3613",
"N1465"
] | N. J. A. Sloane | 2025-11-05T15:35:22 | oeisdata/seq/A000/A000311.seq | 705b817c9b1ebd17844c7fc03ca7537e |
A000312 | a(n) = n^n; number of labeled mappings from n points to themselves (endofunctions). | [
"1",
"1",
"4",
"27",
"256",
"3125",
"46656",
"823543",
"16777216",
"387420489",
"10000000000",
"285311670611",
"8916100448256",
"302875106592253",
"11112006825558016",
"437893890380859375",
"18446744073709551616",
"827240261886336764177",
"39346408075296537575424",
"19784196556... | [
"nonn",
"easy",
"core",
"nice"
] | 358 | 0 | 3 | [
"A000107",
"A000169",
"A000272",
"A000312",
"A001372",
"A001923",
"A002109",
"A007778",
"A007781",
"A007830",
"A008279",
"A008785",
"A008791",
"A019538",
"A048993",
"A055137",
"A055858",
"A056665",
"A062206",
"A066324",
"A066588",
"A081721",
"A083648",
"A085741",
"A13... | [
"M3619",
"N1469"
] | N. J. A. Sloane | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000312.seq | 1d5e493d42a606d0da0a125958860efb |
A000313 | Number of permutations of length n with 3 consecutive ascending pairs. | [
"0",
"0",
"0",
"1",
"4",
"30",
"220",
"1855",
"17304",
"177996",
"2002440",
"24474285",
"323060540",
"4581585866",
"69487385604",
"1122488536715",
"19242660629360",
"348933579412440",
"6673354706262864",
"134252194678935321",
"2834212998777523380",
"62651024183503148470",
... | [
"nonn",
"easy"
] | 93 | 1 | 5 | [
"A000166",
"A000255",
"A000274",
"A000292",
"A000313",
"A001260",
"A001261",
"A010027",
"A065087"
] | [
"M3633",
"N1477"
] | N. J. A. Sloane | 2025-09-22T16:00:13 | oeisdata/seq/A000/A000313.seq | 2e2b31f6d3221770ca79c97183b3f492 |
A000314 | Number of mixed Husimi trees with n nodes; or labeled polygonal cacti with bridges. | [
"1",
"1",
"1",
"4",
"31",
"362",
"5676",
"111982",
"2666392",
"74433564",
"2384579440",
"86248530296",
"3476794472064",
"154579941792256",
"7514932528712896",
"396595845237540600",
"22581060079942183936",
"1379771773100463174608",
"90059660791562688208128",
"6253914166368448348... | [
"nonn"
] | 31 | 0 | 4 | [
"A000083",
"A000237",
"A000314",
"A035082",
"A035349",
"A035357"
] | [
"M3639",
"N1480"
] | N. J. A. Sloane | 2025-11-05T15:35:22 | oeisdata/seq/A000/A000314.seq | 52dbc0b6718bbbc3ecdf04ac7dfdf8ac |
A000315 | Number of reduced Latin squares of order n; also number of labeled loops (quasigroups with an identity element) with a fixed identity element. | [
"1",
"1",
"1",
"4",
"56",
"9408",
"16942080",
"535281401856",
"377597570964258816",
"7580721483160132811489280",
"5363937773277371298119673540771840"
] | [
"nonn",
"hard",
"nice",
"more"
] | 102 | 1 | 4 | [
"A000315",
"A000479",
"A002860",
"A003090",
"A040082",
"A057771",
"A057997"
] | [
"M3690",
"N1508"
] | N. J. A. Sloane | 2025-11-05T15:35:22 | oeisdata/seq/A000/A000315.seq | cd911fe63092e56490de00ce1fd0e2c0 |
A000316 | Two decks each have n kinds of cards, 2 of each kind. The first deck is laid out in order. The second deck is shuffled and laid out next to the first. A match occurs if a card from the second deck is next to a card of the same kind from the first deck. a(n) is the number of ways of achieving no matches. | [
"1",
"0",
"4",
"80",
"4752",
"440192",
"59245120",
"10930514688",
"2649865335040",
"817154768973824",
"312426715251262464",
"145060238642780180480",
"80403174342119992692736",
"52443098500204184915312640",
"39764049487996490505336537088"
] | [
"nonn",
"easy",
"nice"
] | 91 | 0 | 3 | [
"A000166",
"A000316",
"A000459",
"A337302"
] | [
"M3702",
"N1513"
] | N. J. A. Sloane | 2025-11-05T15:35:22 | oeisdata/seq/A000/A000316.seq | 0924e48aa9cbd4d6eaf2b78aa87e56e4 |
A000317 | a(n+1) = a(n)^2 - a(n)*a(n-1) + a(n-1)^2. | [
"1",
"2",
"3",
"7",
"37",
"1159",
"1301767",
"1693089917617",
"2866551265129451657751739",
"8217116155610406522540626640615749228405055996847"
] | [
"nonn"
] | 35 | 1 | 2 | null | null | N. J. A. Sloane | 2025-02-28T10:23:02 | oeisdata/seq/A000/A000317.seq | 75b8447ecb3637e8eee50bc3d6089ad6 |
A000318 | Generalized tangent numbers d(4,n). | [
"4",
"128",
"16384",
"4456448",
"2080374784",
"1483911200768",
"1501108249821184",
"2044143848640217088",
"3605459138582973251584",
"7995891855149741436305408",
"21776918737280678860353961984",
"71454103701490016776039304265728",
"278008871543597996197497752082448384"
] | [
"nonn",
"easy"
] | 46 | 1 | 1 | [
"A000182",
"A000191",
"A000318",
"A000490",
"A349264"
] | [
"M3713",
"N1517"
] | N. J. A. Sloane | 2022-06-22T09:25:26 | oeisdata/seq/A000/A000318.seq | b2bb0b55d4bb26f229d71a9447b9a2d8 |
A000319 | a(n) = floor(b(n)), where b(n) = tan(b(n-1)), b(0)=1. | [
"1",
"1",
"74",
"-1",
"-2",
"-3",
"0",
"1",
"30",
"-2",
"-2",
"29",
"1",
"4",
"-6",
"0",
"1",
"2",
"-1",
"-1",
"-1",
"-1",
"-2",
"-9",
"0",
"0",
"1",
"2",
"-2",
"-35",
"-1",
"-1",
"-1",
"-1",
"-1",
"-1",
"-1",
"-2",
"-3",
"0",
"0",
"1... | [
"sign"
] | 47 | 0 | 3 | [
"A000319",
"A000329",
"A053169",
"A053873",
"A085665",
"A085666",
"A381230",
"A381231"
] | null | N. J. A. Sloane | 2025-03-18T01:39:11 | oeisdata/seq/A000/A000319.seq | a983bbf44d50c731f426b601c29f1c80 |
A000320 | Generalized tangent numbers d(5,n). | [
"4",
"272",
"55744",
"23750912",
"17328937984",
"19313964388352",
"30527905292468224",
"64955605537174126592",
"179013508069217017790464",
"620314831396713435870789632",
"2639743384489464189324523208704",
"13533573366345611477262311433961472",
"82274260343572247169162187576069586944"
] | [
"nonn"
] | 34 | 1 | 1 | [
"A000187",
"A000318",
"A000320",
"A349264",
"A349265"
] | [
"M3722",
"N1521"
] | N. J. A. Sloane | 2021-11-22T04:03:25 | oeisdata/seq/A000/A000320.seq | 4a48d3f8f0d18134bd5f6be973edec95 |
A000321 | H_n(-1/2), where H_n(x) is Hermite polynomial of degree n. | [
"1",
"-1",
"-1",
"5",
"1",
"-41",
"31",
"461",
"-895",
"-6481",
"22591",
"107029",
"-604031",
"-1964665",
"17669471",
"37341149",
"-567425279",
"-627491489",
"19919950975",
"2669742629",
"-759627879679",
"652838174519",
"31251532771999",
"-59976412450835",
"-137759409... | [
"sign",
"easy",
"changed"
] | 98 | 0 | 4 | [
"A000186",
"A000321",
"A062267",
"A144141",
"A293604"
] | [
"M3732",
"N1526"
] | N. J. A. Sloane | 2026-01-14T22:46:36 | oeisdata/seq/A000/A000321.seq | 17f0c45beb170416e112dac69e8ca707 |
A000322 | Pentanacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) + a(n-4) + a(n-5) with a(0) = a(1) = a(2) = a(3) = a(4) = 1. | [
"1",
"1",
"1",
"1",
"1",
"5",
"9",
"17",
"33",
"65",
"129",
"253",
"497",
"977",
"1921",
"3777",
"7425",
"14597",
"28697",
"56417",
"110913",
"218049",
"428673",
"842749",
"1656801",
"3257185",
"6403457",
"12588865",
"24749057",
"48655365",
"95653929",
"... | [
"nonn",
"easy"
] | 87 | 0 | 6 | [
"A000045",
"A000288",
"A000322",
"A000383",
"A001591",
"A060455",
"A186192"
] | [
"M3786",
"N1542"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000322.seq | 86d24322af64322618e83043dc53705c |
A000323 | Let A(n) = #{(i,j): i^2 + j^2 <= n}, V(n) = Pi*n, P(n) = A(n) - V(n); A000099 gives values of n where |P(n)| sets a new record; sequence gives A(A000099(n)). | [
"5",
"9",
"21",
"37",
"69",
"69",
"89",
"137",
"177",
"421",
"481",
"657",
"749",
"885",
"1085",
"1305",
"1353",
"1489",
"1861",
"2617",
"2693",
"3125",
"5249",
"5761",
"7129",
"8109",
"9465",
"9465",
"10717",
"12401",
"12401",
"16237",
"16237",
"248... | [
"nonn"
] | 22 | 1 | 1 | [
"A000036",
"A000092",
"A000099",
"A000223",
"A000323",
"A000413"
] | [
"M3787",
"N1543"
] | N. J. A. Sloane | 2022-02-01T00:53:22 | oeisdata/seq/A000/A000323.seq | 717b82e796749b99331f5bf036b1c861 |
A000324 | A nonlinear recurrence: a(0) = 1, a(1) = 5, a(n) = a(n-1)^2 - 4*a(n-1) + 4 for n>1. | [
"1",
"5",
"9",
"49",
"2209",
"4870849",
"23725150497409",
"562882766124611619513723649",
"316837008400094222150776738483768236006420971486980609"
] | [
"nonn",
"easy"
] | 70 | 0 | 2 | [
"A000032",
"A000058",
"A000215",
"A000289",
"A000324",
"A001566"
] | [
"M3789",
"N1544"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000324.seq | c5dd0e9803096cd99ea9f03afab58de4 |
A000325 | a(n) = 2^n - n. | [
"1",
"1",
"2",
"5",
"12",
"27",
"58",
"121",
"248",
"503",
"1014",
"2037",
"4084",
"8179",
"16370",
"32753",
"65520",
"131055",
"262126",
"524269",
"1048556",
"2097131",
"4194282",
"8388585",
"16777192",
"33554407",
"67108838",
"134217701",
"268435428",
"536... | [
"nonn",
"easy"
] | 228 | 0 | 3 | [
"A000108",
"A000325",
"A001610",
"A002064",
"A005803",
"A006127",
"A008518",
"A047257",
"A048744",
"A066982",
"A081296",
"A133116",
"A160692",
"A184049",
"A184050",
"A186947",
"A299174",
"A323950",
"A323951",
"A349767"
] | null | Rosario Salamone (Rosario.Salamone(AT)risc.uni-linz.ac.at) | 2025-11-10T21:49:43 | oeisdata/seq/A000/A000325.seq | 44142ec83ef46a57e2b03803eb3b0d13 |
A000326 | Pentagonal numbers: a(n) = n*(3*n-1)/2. | [
"0",
"1",
"5",
"12",
"22",
"35",
"51",
"70",
"92",
"117",
"145",
"176",
"210",
"247",
"287",
"330",
"376",
"425",
"477",
"532",
"590",
"651",
"715",
"782",
"852",
"925",
"1001",
"1080",
"1162",
"1247",
"1335",
"1426",
"1520",
"1617",
"1717",
"182... | [
"core",
"nonn",
"easy",
"nice",
"changed"
] | 548 | 0 | 3 | [
"A000326",
"A001318",
"A002411",
"A004736",
"A005449",
"A010815",
"A016777",
"A022288",
"A033568",
"A033570",
"A033579",
"A034856",
"A045943",
"A049452",
"A049453",
"A051340",
"A059845",
"A115067",
"A140090",
"A140091",
"A140672",
"A140673",
"A140674",
"A140675",
"A15... | [
"M3818",
"N1562"
] | N. J. A. Sloane | 2026-01-17T16:40:41 | oeisdata/seq/A000/A000326.seq | 252e2910e62bb6d550965317fa443f5c |
A000327 | Number of partitions into non-integral powers. | [
"1",
"5",
"12",
"23",
"39",
"62",
"91",
"127",
"171",
"228",
"294",
"370",
"461",
"561",
"677",
"811",
"955",
"1121",
"1303",
"1499",
"1719",
"1960",
"2218",
"2499",
"2806",
"3131",
"3485",
"3868",
"4274",
"4706",
"5166",
"5658",
"6175",
"6725",
"7... | [
"nonn"
] | 32 | 3 | 2 | [
"A000148",
"A000158",
"A000160",
"A000327"
] | [
"M3819",
"N1563"
] | N. J. A. Sloane | 2022-07-01T22:18:09 | oeisdata/seq/A000/A000327.seq | 72d35479ab42a60aa397082896118a07 |
A000328 | Number of points of norm <= n^2 in square lattice. | [
"1",
"5",
"13",
"29",
"49",
"81",
"113",
"149",
"197",
"253",
"317",
"377",
"441",
"529",
"613",
"709",
"797",
"901",
"1009",
"1129",
"1257",
"1373",
"1517",
"1653",
"1793",
"1961",
"2121",
"2289",
"2453",
"2629",
"2821",
"3001",
"3209",
"3409",
"3... | [
"nonn",
"easy",
"nice"
] | 100 | 0 | 2 | [
"A000328",
"A000603",
"A046109",
"A051132",
"A057655",
"A093832",
"A093836",
"A093837",
"A255238",
"A302997",
"A305575",
"A305576"
] | [
"M3829",
"N1570"
] | N. J. A. Sloane | 2025-08-19T11:07:34 | oeisdata/seq/A000/A000328.seq | 48dca746e072a6e96cc6f2dfb5a884a5 |
A000329 | Nearest integer to b(n), where b(n) = tan(b(n-1)), b(0) = 1. | [
"1",
"2",
"75",
"-1",
"-1",
"-2",
"1",
"2",
"31",
"-1",
"-2",
"29",
"1",
"5",
"-6",
"1",
"1",
"3",
"-1",
"-1",
"-1",
"-1",
"-1",
"-9",
"1",
"1",
"1",
"2",
"-2",
"-35",
"0",
"0",
"-1",
"-1",
"-1",
"-1",
"-1",
"-1",
"-2",
"1",
"1",
"1",... | [
"sign"
] | 21 | 0 | 2 | [
"A000319",
"A000329"
] | null | N. J. A. Sloane | 2024-11-24T10:15:55 | oeisdata/seq/A000/A000329.seq | f4bc5a6b9ed61c58ff5e0df3e6fbd31c |
A000330 | Square pyramidal numbers: a(n) = 0^2 + 1^2 + 2^2 + ... + n^2 = n*(n+1)*(2*n+1)/6. | [
"0",
"1",
"5",
"14",
"30",
"55",
"91",
"140",
"204",
"285",
"385",
"506",
"650",
"819",
"1015",
"1240",
"1496",
"1785",
"2109",
"2470",
"2870",
"3311",
"3795",
"4324",
"4900",
"5525",
"6201",
"6930",
"7714",
"8555",
"9455",
"10416",
"11440",
"12529",... | [
"nonn",
"easy",
"core",
"nice"
] | 674 | 0 | 3 | [
"A000217",
"A000290",
"A000292",
"A000330",
"A000537",
"A005408",
"A005900",
"A006003",
"A006331",
"A008955",
"A033994",
"A033999",
"A034705",
"A046092",
"A050409",
"A050446",
"A050447",
"A060493",
"A082652",
"A084930",
"A094414",
"A100157",
"A103438",
"A132112",
"A13... | [
"M3844",
"N1574"
] | N. J. A. Sloane | 2025-12-29T15:25:33 | oeisdata/seq/A000/A000330.seq | d948823788f094379aa4ec80f93a56cb |
A000331 | Related to zeros of Bessel function. | [
"5",
"14",
"1026",
"4324",
"311387",
"6425694",
"579783114",
"4028104212",
"7315072725560",
"61358264615344",
"9569450876916944",
"1632353370882506848",
"1365475358484643531856",
"15211641461623992544160",
"74766806258361827981250240",
"936580261005146914634459520",
"6083678228249789... | [
"nonn"
] | 36 | 4 | 1 | [
"A000331",
"A158616"
] | [
"M3848",
"N1575"
] | N. J. A. Sloane | 2024-11-01T21:27:07 | oeisdata/seq/A000/A000331.seq | 2eb1e652acef157fb97cc383eb217f3c |
A000332 | Binomial coefficient binomial(n,4) = n*(n-1)*(n-2)*(n-3)/24. | [
"0",
"0",
"0",
"0",
"1",
"5",
"15",
"35",
"70",
"126",
"210",
"330",
"495",
"715",
"1001",
"1365",
"1820",
"2380",
"3060",
"3876",
"4845",
"5985",
"7315",
"8855",
"10626",
"12650",
"14950",
"17550",
"20475",
"23751",
"27405",
"31465",
"35960",
"40920... | [
"nonn",
"easy",
"nice",
"changed"
] | 498 | 0 | 6 | [
"A000217",
"A000292",
"A000332",
"A000389",
"A000579",
"A000580",
"A000581",
"A000582",
"A000583",
"A006003",
"A006008",
"A006322",
"A006325",
"A007318",
"A014820",
"A025036",
"A053126",
"A053134",
"A075733",
"A092181",
"A092182",
"A092183",
"A099174",
"A104712",
"A15... | [
"M3853",
"N1578"
] | N. J. A. Sloane | 2026-01-15T10:22:20 | oeisdata/seq/A000/A000332.seq | e5c1e8838beaeba3d6162bf4ba450d2e |
A000333 | Number of partitions into non-integral powers. | [
"1",
"5",
"15",
"40",
"98",
"237",
"534",
"1185",
"2554",
"5391",
"11117",
"22556",
"44858",
"88000",
"170107",
"324547",
"611755",
"1140382",
"2103554",
"3842826",
"6955918",
"12483075",
"22220002",
"39248230",
"68819781",
"119839422",
"207304370",
"356356801",... | [
"nonn"
] | 20 | 1 | 2 | null | [
"M3856",
"N1579"
] | N. J. A. Sloane | 2022-02-03T22:42:15 | oeisdata/seq/A000/A000333.seq | b96098dd7e2346e7c5ca7b146d04479b |
A000334 | Number of 4-dimensional partitions of n. | [
"1",
"5",
"15",
"45",
"120",
"326",
"835",
"2145",
"5345",
"13220",
"32068",
"76965",
"181975",
"425490",
"982615",
"2245444",
"5077090",
"11371250",
"25235790",
"55536870",
"121250185",
"262769080",
"565502405",
"1209096875",
"2569270050",
"5427963902",
"11404408... | [
"nonn",
"nice"
] | 53 | 1 | 2 | [
"A000219",
"A000293",
"A000334",
"A000390",
"A002974",
"A007714",
"A050340",
"A096751"
] | [
"M3858",
"N1580"
] | N. J. A. Sloane | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000334.seq | 5bf4e756b4f0fd0088ffa3c84e6762be |
A000335 | Euler transform of A000292. | [
"1",
"5",
"15",
"45",
"120",
"331",
"855",
"2214",
"5545",
"13741",
"33362",
"80091",
"189339",
"442799",
"1023192",
"2340904",
"5302061",
"11902618",
"26488454",
"58479965",
"128120214",
"278680698",
"602009786",
"1292027222",
"2755684669",
"5842618668",
"1231717... | [
"nonn",
"nice"
] | 55 | 1 | 2 | [
"A000041",
"A000219",
"A000294",
"A000335",
"A000391",
"A000417",
"A000428",
"A255965"
] | [
"M3859",
"N1581"
] | N. J. A. Sloane | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000335.seq | 33df722ea095240f8837df84412605f4 |
A000336 | a(n) = a(n-1)*a(n-2)*a(n-3)*a(n-4); for n < 5, a(n) = n. | [
"1",
"2",
"3",
"4",
"24",
"576",
"165888",
"9172942848",
"21035720123168587776",
"18437563379178327736384102280592359424",
"590180110002114158896983994712576414865667267958188575935810179040280576"
] | [
"nonn"
] | 30 | 1 | 2 | [
"A000301",
"A000308",
"A000336",
"A001631",
"A003586",
"A251656"
] | null | N. J. A. Sloane | 2019-01-21T13:02:08 | oeisdata/seq/A000/A000336.seq | d3f8d2c107bedb67004e9f322aa05c45 |
A000337 | a(n) = (n-1)*2^n + 1. | [
"0",
"1",
"5",
"17",
"49",
"129",
"321",
"769",
"1793",
"4097",
"9217",
"20481",
"45057",
"98305",
"212993",
"458753",
"983041",
"2097153",
"4456449",
"9437185",
"19922945",
"41943041",
"88080385",
"184549377",
"385875969",
"805306369",
"1677721601",
"3489660929... | [
"nonn",
"easy",
"nice"
] | 259 | 0 | 3 | [
"A000079",
"A000295",
"A000337",
"A001787",
"A003338",
"A008292",
"A014915",
"A023758",
"A036799",
"A048472",
"A066185",
"A077436",
"A209359",
"A336725"
] | [
"M3874",
"N1587"
] | N. J. A. Sloane | 2025-11-16T11:47:50 | oeisdata/seq/A000/A000337.seq | 2d16d4f7eef5eef83c2ad644c680a968 |
A000338 | Expansion of x^3*(5-2*x)*(1-x^3)/(1-x)^4. | [
"5",
"18",
"42",
"75",
"117",
"168",
"228",
"297",
"375",
"462",
"558",
"663",
"777",
"900",
"1032",
"1173",
"1323",
"1482",
"1650",
"1827",
"2013",
"2208",
"2412",
"2625",
"2847",
"3078",
"3318",
"3567",
"3825",
"4092",
"4368",
"4653",
"4947",
"5250... | [
"nonn",
"easy"
] | 50 | 3 | 1 | null | [
"M3877",
"N1589"
] | N. J. A. Sloane | 2024-04-22T07:16:34 | oeisdata/seq/A000/A000338.seq | a0f3faee6f3df7aa45bd187e4f6b0ca8 |
A000339 | Number of partitions into non-integral powers. | [
"1",
"5",
"18",
"45",
"100",
"185",
"323",
"522",
"804",
"1180",
"1687",
"2322",
"3139",
"4146",
"5377",
"6859",
"8645",
"10733",
"13203",
"16058",
"19356",
"23132",
"27460",
"32330",
"37846",
"44031",
"50954",
"58637",
"67203",
"76613",
"87021",
"98443"... | [
"nonn"
] | 26 | 2 | 2 | null | [
"M3879",
"N1590"
] | N. J. A. Sloane | 2023-04-10T12:50:31 | oeisdata/seq/A000/A000339.seq | e60c9e52edab636f3cfbc50ae10e8359 |
A000340 | a(0)=1, a(n) = 3*a(n-1) + n + 1. | [
"1",
"5",
"18",
"58",
"179",
"543",
"1636",
"4916",
"14757",
"44281",
"132854",
"398574",
"1195735",
"3587219",
"10761672",
"32285032",
"96855113",
"290565357",
"871696090",
"2615088290",
"7845264891",
"23535794695",
"70607384108",
"211822152348",
"635466457069"
] | [
"nonn",
"easy"
] | 94 | 0 | 2 | [
"A000340",
"A003462",
"A008971",
"A014915",
"A106516",
"A142963",
"A156919",
"A156920",
"A156921",
"A156922",
"A156923",
"A156924",
"A156925",
"A156927",
"A156933"
] | [
"M3882",
"N1592"
] | N. J. A. Sloane, Simon Plouffe | 2025-09-18T12:16:48 | oeisdata/seq/A000/A000340.seq | ed69b6e307b27d92dc63f7c62c9ff53d |
A000341 | Number of ways to pair up {1..2n} so sum of each pair is prime. | [
"1",
"2",
"3",
"6",
"26",
"96",
"210",
"1106",
"3759",
"12577",
"74072",
"423884",
"2333828",
"16736611",
"99838851",
"630091746",
"4525325020",
"38848875650",
"342245714017",
"3335164762941",
"31315463942337",
"241353231085002",
"2350106537365732",
"17903852593938447",... | [
"nonn",
"nice"
] | 44 | 1 | 2 | [
"A000341",
"A005326",
"A009692"
] | null | S. J. Greenfield (greenfie(AT)math.rutgers.edu) | 2023-09-22T05:15:14 | oeisdata/seq/A000/A000341.seq | 4aa7944777d0b621dd9d448fbabd79b0 |
A000342 | Number of n-node rooted trees of height 5. | [
"0",
"0",
"0",
"0",
"0",
"1",
"5",
"19",
"61",
"180",
"498",
"1323",
"3405",
"8557",
"21103",
"51248",
"122898",
"291579",
"685562",
"1599209",
"3705122",
"8532309",
"19543867",
"44552066",
"101124867",
"228640542",
"515125815",
"1156829459",
"2590247002",
"... | [
"nonn"
] | 38 | 1 | 7 | [
"A000342",
"A034781"
] | [
"M3884",
"N1594"
] | N. J. A. Sloane | 2022-06-01T14:44:37 | oeisdata/seq/A000/A000342.seq | a7f1bdb8b2cb30c75937d1932bc97252 |
A000343 | 5th power of rooted tree enumerator; number of linear forests of 5 rooted trees. | [
"1",
"5",
"20",
"70",
"230",
"721",
"2200",
"6575",
"19385",
"56575",
"163952",
"472645",
"1357550",
"3888820",
"11119325",
"31753269",
"90603650",
"258401245",
"736796675",
"2100818555",
"5990757124",
"17087376630",
"48753542665",
"139155765455",
"397356692275",
"1... | [
"nonn"
] | 33 | 5 | 2 | [
"A000081",
"A000106",
"A000242",
"A000300",
"A000343",
"A000395",
"A339067"
] | [
"M3901",
"N1601"
] | N. J. A. Sloane | 2021-01-03T04:31:08 | oeisdata/seq/A000/A000343.seq | cc352c9075973a4b73042a5afbd2daca |
A000344 | a(n) = 5*binomial(2n, n-2)/(n+3). | [
"1",
"5",
"20",
"75",
"275",
"1001",
"3640",
"13260",
"48450",
"177650",
"653752",
"2414425",
"8947575",
"33266625",
"124062000",
"463991880",
"1739969550",
"6541168950",
"24647883000",
"93078189750",
"352207870014",
"1335293573130",
"5071418015120",
"19293438101000",
... | [
"nonn",
"easy"
] | 166 | 2 | 2 | [
"A000108",
"A000245",
"A000344",
"A000588",
"A001392",
"A001622",
"A002057",
"A003517",
"A003518",
"A003519",
"A009766",
"A030237",
"A033184",
"A047072",
"A059365",
"A099039",
"A106566",
"A130020"
] | [
"M3904",
"N1602"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000344.seq | ae8c02c4ee2765bbcb4d874b629ffcdb |
A000345 | Number of partitions into non-integral powers. | [
"1",
"5",
"22",
"71",
"186",
"427",
"888",
"1704",
"3053",
"5203",
"8476",
"13318",
"20265",
"29946",
"43254",
"61171",
"84832",
"115713",
"155382",
"205779",
"269065",
"347906",
"445001",
"563685",
"707637",
"881042",
"1088339",
"1335019",
"1626233",
"19687... | [
"nonn"
] | 18 | 3 | 2 | null | [
"M3918",
"N1610"
] | N. J. A. Sloane | 2017-08-06T21:47:50 | oeisdata/seq/A000/A000345.seq | 488972b148230f3a1f437083c27814d3 |
A000346 | a(n) = 2^(2*n+1) - binomial(2*n+1, n+1). | [
"1",
"5",
"22",
"93",
"386",
"1586",
"6476",
"26333",
"106762",
"431910",
"1744436",
"7036530",
"28354132",
"114159428",
"459312152",
"1846943453",
"7423131482",
"29822170718",
"119766321572",
"480832549478",
"1929894318332",
"7744043540348",
"31067656725032",
"12461368... | [
"nonn",
"easy"
] | 161 | 0 | 2 | [
"A000070",
"A000108",
"A000302",
"A000346",
"A001700",
"A001791",
"A007008",
"A007318",
"A008549",
"A011782",
"A014137",
"A014318",
"A025047",
"A027306",
"A032443",
"A033504",
"A038806",
"A045621",
"A053754",
"A053979",
"A055217",
"A058622",
"A058893",
"A068551",
"A06... | [
"M3920",
"N1611"
] | N. J. A. Sloane, Wolfdieter Lang | 2025-12-11T12:38:05 | oeisdata/seq/A000/A000346.seq | b96f7bd0335f8cc858aa463dfde90237 |
A000347 | Number of partitions into non-integral powers. | [
"1",
"5",
"24",
"84",
"251",
"653",
"1543",
"3341",
"6763",
"12879",
"23446",
"40883",
"68757",
"111976",
"177358",
"273926",
"413784",
"612430",
"889959",
"1271709",
"1789841",
"2483779",
"3402623",
"4605954",
"6166614",
"8171174",
"10724604",
"13950011",
"17... | [
"nonn"
] | 22 | 4 | 2 | null | [
"M3929",
"N1616"
] | N. J. A. Sloane | 2024-07-30T02:18:11 | oeisdata/seq/A000/A000347.seq | a7b7563920f7eba4035c3a0793323536 |
A000348 | Number of ways to pair up {1^2, 2^2, ..., (2n)^2 } so sum of each pair is prime. | [
"1",
"1",
"2",
"4",
"12",
"9",
"72",
"160",
"428",
"2434",
"3011",
"10337",
"126962",
"264182",
"783550",
"5004266",
"34340141",
"176302123",
"1188146567",
"4457147441",
"7845512385",
"132253267889",
"1004345333251",
"3865703506342",
"40719018858150",
"2139825613769... | [
"nonn",
"nice"
] | 33 | 1 | 3 | [
"A000341",
"A000348"
] | null | S. J. Greenfield (greenfie(AT)math.rutgers.edu) | 2016-12-18T22:45:15 | oeisdata/seq/A000/A000348.seq | c0ac83d1c0b412cfab6218d37ac686ef |
A000349 | One-half the number of permutations of length n with exactly 2 rising or falling successions. | [
"0",
"0",
"0",
"1",
"5",
"24",
"128",
"835",
"6423",
"56410",
"554306",
"6016077",
"71426225",
"920484892",
"12793635300",
"190730117959",
"3035659077083",
"51371100102990",
"920989078354838",
"17437084517068465",
"347647092476801301",
"7280060180210901232",
"159755491837... | [
"nonn"
] | 23 | 0 | 5 | [
"A000130",
"A000349",
"A002464",
"A010028",
"A086852",
"A086853"
] | [
"M3932",
"N1617"
] | N. J. A. Sloane | 2021-12-19T09:29:55 | oeisdata/seq/A000/A000349.seq | 238dbe636e485abaaeaa8c55f1677297 |
A000350 | Numbers m such that Fibonacci(m) ends with m. | [
"0",
"1",
"5",
"25",
"29",
"41",
"49",
"61",
"65",
"85",
"89",
"101",
"125",
"145",
"149",
"245",
"265",
"365",
"385",
"485",
"505",
"601",
"605",
"625",
"649",
"701",
"725",
"745",
"749",
"845",
"865",
"965",
"985",
"1105",
"1205",
"1249",
"13... | [
"nonn",
"base",
"easy",
"nice"
] | 69 | 1 | 3 | [
"A000045",
"A000350",
"A023172",
"A038546",
"A050816",
"A052000"
] | [
"M3935",
"N1619"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000350.seq | 8be74c1757c917082ae16e33e0c02aff |
A000351 | Powers of 5: a(n) = 5^n. | [
"1",
"5",
"25",
"125",
"625",
"3125",
"15625",
"78125",
"390625",
"1953125",
"9765625",
"48828125",
"244140625",
"1220703125",
"6103515625",
"30517578125",
"152587890625",
"762939453125",
"3814697265625",
"19073486328125",
"95367431640625",
"476837158203125",
"23841857910... | [
"easy",
"nonn",
"nice"
] | 185 | 0 | 2 | [
"A000351",
"A001021",
"A001076",
"A003463",
"A005054",
"A006495",
"A006496",
"A008776",
"A009969",
"A013620",
"A013710",
"A014261",
"A020858",
"A038220",
"A067497",
"A085449",
"A159991",
"A279511"
] | [
"M3937",
"N1620"
] | N. J. A. Sloane | 2025-12-13T17:08:16 | oeisdata/seq/A000/A000351.seq | f9ea35e5bc9bb21384452a43c9f78830 |
A000352 | One half of the number of permutations of [n] such that the differences have three runs with the same signs. | [
"5",
"29",
"118",
"418",
"1383",
"4407",
"13736",
"42236",
"128761",
"390385",
"1179354",
"3554454",
"10696139",
"32153963",
"96592972",
"290041072",
"870647517",
"2612991141",
"7841070590",
"23527406090",
"70590606895",
"211788597919",
"635399348208",
"1906265153508",
... | [
"nonn"
] | 65 | 4 | 1 | [
"A000352",
"A000486",
"A000506",
"A008970"
] | [
"M3954",
"N1629"
] | N. J. A. Sloane | 2023-02-08T16:40:07 | oeisdata/seq/A000/A000352.seq | afc963aa982492e75a7f5105f0561a2d |
A000353 | Primes p == 7, 19, 23 (mod 40) such that (p-1)/2 is also prime. | [
"7",
"23",
"47",
"59",
"167",
"179",
"263",
"383",
"503",
"863",
"887",
"983",
"1019",
"1367",
"1487",
"1619",
"1823",
"2063",
"2099",
"2207",
"2447",
"2459",
"2579",
"2819",
"2903",
"3023",
"3167",
"3623",
"3779",
"3863",
"4007",
"4127",
"4139",
"42... | [
"nonn"
] | 36 | 1 | 1 | [
"A000353",
"A001913",
"A005385",
"A006883"
] | null | Robert A. J. Matthews | 2024-01-20T03:53:00 | oeisdata/seq/A000/A000353.seq | 552ca3eda7a5934a7cb2831951a25574 |
A000354 | Expansion of e.g.f. exp(-x)/(1-2*x). | [
"1",
"1",
"5",
"29",
"233",
"2329",
"27949",
"391285",
"6260561",
"112690097",
"2253801941",
"49583642701",
"1190007424825",
"30940193045449",
"866325405272573",
"25989762158177189",
"831672389061670049",
"28276861228096781665",
"1017967004211484139941",
"3868274616003639731775... | [
"nonn",
"easy",
"nice"
] | 168 | 0 | 3 | [
"A000166",
"A000354",
"A008290",
"A061714",
"A113012",
"A263895",
"A320032"
] | [
"M3957",
"N1631"
] | N. J. A. Sloane | 2025-11-15T11:11:32 | oeisdata/seq/A000/A000354.seq | 9cf8d9aaec502cf2ed7a28b1a8433fd4 |
A000355 | Primes p == 3, 9, 11 (mod 20) such that 2p+1 is also prime. | [
"3",
"11",
"23",
"29",
"83",
"89",
"131",
"191",
"251",
"431",
"443",
"491",
"509",
"683",
"743",
"809",
"911",
"1031",
"1049",
"1103",
"1223",
"1229",
"1289",
"1409",
"1451",
"1511",
"1583",
"1811",
"1889",
"1931",
"2003",
"2063",
"2069",
"2129",
... | [
"nonn",
"easy"
] | 30 | 1 | 1 | [
"A000353",
"A000355",
"A005384"
] | null | Robert A. J. Matthews | 2023-10-31T15:58:06 | oeisdata/seq/A000/A000355.seq | 9cbe8ae105ee8910fe53180dccaef8a6 |
A000356 | Number of rooted cubic maps with 2n nodes and a distinguished Hamiltonian cycle: (2n)!(2n+1)! / (n!^2*(n+1)!(n+2)!). | [
"1",
"5",
"35",
"294",
"2772",
"28314",
"306735",
"3476330",
"40831076",
"493684828",
"6114096716",
"77266057400",
"993420738000",
"12964140630900",
"171393565105575",
"2291968851019650",
"30961684478686500",
"422056646314726500"
] | [
"easy",
"nonn",
"nice"
] | 68 | 1 | 2 | [
"A000264",
"A000309",
"A000356",
"A000891",
"A001700",
"A005568",
"A056220",
"A073165",
"A102539"
] | [
"M3978",
"N1647"
] | N. J. A. Sloane, Simon Plouffe | 2023-02-24T02:05:46 | oeisdata/seq/A000/A000356.seq | 56b2b63bb9a2c2b17caee17c57823505 |
A000357 | Number of 5-level labeled rooted trees with n leaves. | [
"1",
"1",
"5",
"35",
"315",
"3455",
"44590",
"660665",
"11035095",
"204904830",
"4183174520",
"93055783320",
"2238954627848",
"57903797748386",
"1601122732128779",
"47120734323344439",
"1470076408565099152",
"48449426629560437576",
"1681560512531504058350",
"6129305488611979679... | [
"nonn",
"easy"
] | 57 | 0 | 3 | [
"A000110",
"A000258",
"A000307",
"A000357",
"A000405",
"A001669",
"A039811",
"A039813",
"A144150"
] | [
"M3979",
"N1648"
] | N. J. A. Sloane | 2025-11-09T10:32:42 | oeisdata/seq/A000/A000357.seq | 00e54afe26f37655d2854327705fa123 |
A000358 | Number of binary necklaces of length n with no subsequence 00, excluding the necklace "0". | [
"1",
"2",
"2",
"3",
"3",
"5",
"5",
"8",
"10",
"15",
"19",
"31",
"41",
"64",
"94",
"143",
"211",
"329",
"493",
"766",
"1170",
"1811",
"2787",
"4341",
"6713",
"10462",
"16274",
"25415",
"39651",
"62075",
"97109",
"152288",
"238838",
"375167",
"589527... | [
"nonn",
"easy"
] | 145 | 1 | 2 | [
"A000358",
"A006206",
"A032190",
"A093305",
"A280218",
"A320341"
] | null | Frank Ruskey | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000358.seq | 9883cbd4b3e4a9d712744a921e1fc5a3 |
A000359 | Coefficients of iterated exponentials. | [
"1",
"5",
"40",
"440",
"6170",
"105315",
"2120610",
"49242470",
"1296133195",
"38152216495",
"1242274374380",
"44345089721923",
"1722416374173854",
"72330102999829054",
"3265871028909088036",
"157797437377747327987",
"8124524883679977475839",
"444098724261935142753430"
] | [
"nonn"
] | 38 | 1 | 2 | [
"A000268",
"A000310",
"A000359",
"A000406",
"A001765",
"A003713",
"A039817"
] | [
"M3991",
"N1654"
] | N. J. A. Sloane | 2022-02-11T12:42:57 | oeisdata/seq/A000/A000359.seq | e34fd83c1346dab87c9ed8d0dad4995d |
A000360 | Distribution of nonempty triangles inside a fractal rep-4-tile. | [
"1",
"0",
"1",
"1",
"1",
"1",
"2",
"0",
"2",
"2",
"2",
"1",
"3",
"1",
"2",
"1",
"2",
"2",
"4",
"1",
"4",
"3",
"3",
"1",
"4",
"2",
"4",
"2",
"3",
"2",
"3",
"0",
"3",
"3",
"4",
"2",
"6",
"3",
"5",
"2",
"5",
"4",
"7",
"2",
"6",
"... | [
"nonn",
"nice",
"easy",
"eigen",
"look"
] | 131 | 0 | 7 | [
"A000360",
"A000361",
"A000876",
"A001222",
"A002487",
"A057078",
"A125184",
"A284553",
"A284556",
"A284565",
"A287729",
"A287730"
] | null | M. Jeremie Lafitte (Levitas) | 2025-09-13T23:25:45 | oeisdata/seq/A000/A000360.seq | dfe2d094a9188b73cc87203d87ae2d68 |
A000361 | From a fractal set of positive Lebesgue measure, a self-replicating tiling with holes, the 4-reptile following the 2-reptile of Paul Levy. | [
"1",
"0",
"2",
"1",
"1",
"2",
"5",
"0",
"10",
"6",
"3",
"2",
"19",
"2",
"10",
"1",
"5",
"10",
"89",
"1",
"170",
"28",
"7",
"2",
"71",
"12",
"170",
"5",
"25",
"10",
"21",
"0",
"42",
"26",
"51",
"10",
"1251",
"38",
"682",
"6",
"301",
"1... | [
"nonn",
"eigen",
"nice",
"more"
] | 23 | 0 | 3 | [
"A000360",
"A000361",
"A000876"
] | null | M. Jeremie Lafitte (Levitas) | 2017-04-20T12:09:14 | oeisdata/seq/A000/A000361.seq | 7dbe2ecd9c52fb6b0c977d559ec61fe1 |
A000362 | Generalized class numbers c_(n,2). | [
"5",
"57",
"352",
"1280",
"3522",
"7970",
"15872",
"29184",
"49410",
"79042",
"122400",
"180224",
"257314",
"362340",
"492032",
"655360",
"867588",
"1117314",
"1420320",
"1803264",
"2237380",
"2745154",
"3380736",
"4080640",
"4881250",
"5874150",
"6928416",
"812... | [
"nonn",
"easy"
] | 36 | 1 | 1 | [
"A000233",
"A000362",
"A000508"
] | [
"M4016",
"N1664"
] | N. J. A. Sloane | 2024-10-05T16:29:46 | oeisdata/seq/A000/A000362.seq | 96cb85cef45f2bc00e9b60a47262dd5b |
A000363 | Number of permutations of [n] with exactly 2 increasing runs of length at least 2. | [
"5",
"61",
"479",
"3111",
"18270",
"101166",
"540242",
"2819266",
"14494859",
"73802835",
"373398489",
"1881341265",
"9453340172",
"47417364268",
"237571096820",
"1189405165908",
"5951965440609",
"29775517732665",
"148927275340835",
"744793282001995"
] | [
"nonn",
"easy"
] | 33 | 4 | 1 | [
"A000363",
"A008971",
"A160486"
] | [
"M4018",
"N1666"
] | N. J. A. Sloane | 2024-11-09T17:01:01 | oeisdata/seq/A000/A000363.seq | ce83338503e29f51a8c0a72862ac7b41 |
A000364 | Euler (or secant or "Zig") numbers: e.g.f. (even powers only) sec(x) = 1/cos(x). | [
"1",
"1",
"5",
"61",
"1385",
"50521",
"2702765",
"199360981",
"19391512145",
"2404879675441",
"370371188237525",
"69348874393137901",
"15514534163557086905",
"4087072509293123892361",
"1252259641403629865468285",
"441543893249023104553682821",
"177519391579539289436664789665"
] | [
"nonn",
"easy",
"nice",
"core"
] | 555 | 0 | 3 | [
"A000007",
"A000111",
"A000182",
"A000281",
"A000364",
"A000464",
"A000816",
"A002105",
"A002436",
"A002438",
"A002439",
"A011248",
"A013525",
"A019669",
"A028296",
"A034947",
"A060058",
"A060074",
"A060075",
"A076552",
"A079144",
"A122045",
"A125053",
"A158690",
"A16... | [
"M4019",
"N1667"
] | N. J. A. Sloane | 2025-12-20T13:20:13 | oeisdata/seq/A000/A000364.seq | c4bca2614cfc3f68b75a1e1badb54a89 |
A000365 | Number of genus 0 rooted planar maps with 4 faces and n vertices. | [
"5",
"93",
"1030",
"8885",
"65954",
"442610",
"2762412",
"16322085",
"92400330",
"505403910",
"2687477780",
"13957496098",
"71053094420",
"355548314180",
"1752827693528",
"8529176056965",
"41026491589722",
"195327793313790",
"921451498774660",
"4311086414580022",
"20019238138... | [
"nonn"
] | 33 | 3 | 1 | [
"A000365",
"A269920",
"A270408"
] | [
"M4022",
"N1669"
] | N. J. A. Sloane | 2021-03-27T23:02:35 | oeisdata/seq/A000/A000365.seq | 7b806889b3ae64f0ad8ba0a1fe078b65 |
A000366 | Genocchi numbers of second kind (A005439) divided by 2^(n-1). | [
"1",
"1",
"2",
"7",
"38",
"295",
"3098",
"42271",
"726734",
"15366679",
"391888514",
"11860602415",
"420258768950",
"17233254330343",
"809698074358250",
"43212125903877439",
"2599512037272630686",
"175079893678534943287",
"13122303354155987156306",
"1088559958829010054171343",
... | [
"nonn",
"easy",
"nice"
] | 125 | 1 | 3 | [
"A000366",
"A001469",
"A005439",
"A014784",
"A130168",
"A130169",
"A239894"
] | null | Don Knuth, N. J. A. Sloane | 2025-10-20T12:13:06 | oeisdata/seq/A000/A000366.seq | 55e388d65fad010f301422030bc181c2 |
A000367 | Numerators of Bernoulli numbers B_2n. | [
"1",
"1",
"-1",
"1",
"-1",
"5",
"-691",
"7",
"-3617",
"43867",
"-174611",
"854513",
"-236364091",
"8553103",
"-23749461029",
"8615841276005",
"-7709321041217",
"2577687858367",
"-26315271553053477373",
"2929993913841559",
"-261082718496449122051",
"1520097643918070802691",
... | [
"sign",
"frac",
"nice"
] | 206 | 0 | 6 | [
"A000367",
"A002445",
"A002882",
"A003245",
"A027641",
"A027642",
"A127187",
"A127188"
] | [
"M4039",
"N1677"
] | N. J. A. Sloane | 2025-11-05T15:21:38 | oeisdata/seq/A000/A000367.seq | 81464e1c1ceb792cc8fc20896e671bdf |
A000368 | Number of connected graphs with one cycle of length 4. | [
"1",
"1",
"4",
"9",
"28",
"71",
"202",
"542",
"1507",
"4114",
"11381",
"31349",
"86845",
"240567",
"668553",
"1860361",
"5188767",
"14495502",
"40572216",
"113743293",
"319405695",
"898288484",
"2530058013",
"7135848125",
"20152898513",
"56986883801"
] | [
"nonn"
] | 79 | 4 | 3 | [
"A000081",
"A000226",
"A000368",
"A001429",
"A005703",
"A058879",
"A217781"
] | [
"M3365",
"N1356"
] | N. J. A. Sloane | 2024-07-28T16:49:54 | oeisdata/seq/A000/A000368.seq | ada3f802f5e92c662ab6d557f47e57f2 |
A000369 | Triangle of numbers related to triangle A049213; generalization of Stirling numbers of second kind A008277, Bessel triangle A001497. | [
"1",
"3",
"1",
"21",
"9",
"1",
"231",
"111",
"18",
"1",
"3465",
"1785",
"345",
"30",
"1",
"65835",
"35595",
"7650",
"825",
"45",
"1",
"1514205",
"848925",
"196245",
"24150",
"1680",
"63",
"1",
"40883535",
"23586255",
"5755050",
"775845",
"62790",
"30... | [
"easy",
"nonn",
"tabl"
] | 72 | 1 | 2 | [
"A000369",
"A004747",
"A008545",
"A016036",
"A132163"
] | null | Wolfdieter Lang | 2025-09-22T16:00:13 | oeisdata/seq/A000/A000369.seq | 30ff4d06eb0c87f96fadb2a5568ffa7f |
A000370 | Number of NPN-equivalence classes of Boolean functions of n or fewer variables. | [
"1",
"2",
"4",
"14",
"222",
"616126",
"200253952527184",
"263735716028826576482466871188128",
"5609038300883759793482640992086670939164957990135057216103303119630336"
] | [
"nonn",
"nice"
] | 74 | 0 | 2 | null | [
"M1287",
"N0494"
] | N. J. A. Sloane | 2025-01-12T09:17:29 | oeisdata/seq/A000/A000370.seq | 4892b9242718b39d15b4d0d78e707ee6 |
A000371 | a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(n,k)*2^(2^k). | [
"2",
"2",
"10",
"218",
"64594",
"4294642034",
"18446744047940725978",
"340282366920938463334247399005993378250",
"115792089237316195423570985008687907850547725730273056332267095982282337798562"
] | [
"nonn",
"easy",
"nice"
] | 160 | 0 | 1 | [
"A000110",
"A000371",
"A001146",
"A002110",
"A003465",
"A055154",
"A076078",
"A163353",
"A186021",
"A381683"
] | [
"M0385",
"N0145"
] | N. J. A. Sloane | 2025-11-05T15:35:22 | oeisdata/seq/A000/A000371.seq | de98492ec88ddefa08628edbf1c8fb11 |
A000372 | Dedekind numbers or Dedekind's problem: number of monotone Boolean functions of n variables, number of antichains of subsets of an n-set, number of elements in a free distributive lattice on n generators, number of Sperner families. | [
"2",
"3",
"6",
"20",
"168",
"7581",
"7828354",
"2414682040998",
"56130437228687557907788",
"286386577668298411128469151667598498812366"
] | [
"nonn",
"hard",
"more",
"nice"
] | 347 | 0 | 1 | [
"A000372",
"A003182",
"A006126",
"A006602",
"A007153",
"A014466",
"A059119",
"A261005",
"A293606",
"A293993",
"A304996",
"A305000",
"A305844",
"A306505",
"A317674",
"A319721",
"A320449",
"A321679"
] | [
"M0817",
"N0309"
] | N. J. A. Sloane | 2025-11-19T14:28:33 | oeisdata/seq/A000/A000372.seq | b23cd35a7611292003720f72a27e542e |
A000373 | Conjectured dimension of a module associated with the free commutative Moufang loop with n generators. | [
"0",
"0",
"1",
"8",
"44",
"214",
"1000",
"4592",
"20888",
"94846",
"434973",
"2042836",
"9979086",
"51460622",
"283839957",
"1688139424",
"10859199656",
"75338888918",
"560740210491",
"4445766353604",
"37329808482989",
"330143634313064",
"3064464030121369"
] | [
"nonn"
] | 32 | 1 | 4 | [
"A000373",
"A152123"
] | null | N. J. A. Sloane | 2024-09-23T10:21:31 | oeisdata/seq/A000/A000373.seq | fafbb981c78a1e9f456874e279e36203 |
A000374 | Number of cycles (mod n) under doubling map. | [
"1",
"1",
"2",
"1",
"2",
"2",
"3",
"1",
"3",
"2",
"2",
"2",
"2",
"3",
"5",
"1",
"3",
"3",
"2",
"2",
"6",
"2",
"3",
"2",
"3",
"2",
"4",
"3",
"2",
"5",
"7",
"1",
"5",
"3",
"6",
"3",
"2",
"2",
"5",
"2",
"3",
"6",
"4",
"2",
"8",
"... | [
"nonn"
] | 46 | 1 | 3 | [
"A000005",
"A000374",
"A023135",
"A023142",
"A037226",
"A081844"
] | null | Shel Kaphan | 2025-04-25T03:06:11 | oeisdata/seq/A000/A000374.seq | 80bc47d18b0709606e2a0dce7d6a0f17 |
A000375 | Topswops (1): start by shuffling n cards labeled 1..n. If top card is m, reverse order of top m cards, then repeat. a(n) is the maximal number of steps before top card is 1. | [
"0",
"1",
"2",
"4",
"7",
"10",
"16",
"22",
"30",
"38",
"51",
"65",
"80",
"101",
"113",
"139",
"159",
"191",
"221"
] | [
"nonn",
"hard",
"nice",
"more"
] | 90 | 1 | 3 | [
"A000375",
"A000376",
"A123398"
] | null | Bill Blewett and Mike Toepke [mtoepke(AT)microsoft.com] | 2025-11-05T15:35:22 | oeisdata/seq/A000/A000375.seq | 4d9a164ec3936c91242eaa2a9b51a952 |
A000376 | Topswops (2): start by shuffling n cards labeled 1..n. If the top card is m, reverse the order of the top m cards. Repeat until 1 gets to the top, then stop. Suppose the whole deck is now sorted (if not, discard this case). a(n) is the maximal number of steps before 1 got to the top. | [
"0",
"1",
"2",
"4",
"7",
"10",
"16",
"22",
"30",
"38",
"51",
"63",
"80",
"101",
"112",
"130",
"159",
"191",
"207",
"231"
] | [
"nonn",
"hard",
"nice",
"more"
] | 57 | 1 | 3 | [
"A000375",
"A000376",
"A174498"
] | null | Bill Blewett, Mike Toepke [ mtoepke(AT)microsoft.com ] | 2024-06-19T12:43:08 | oeisdata/seq/A000/A000376.seq | bb9be48383eb2fdcc5af179a564536f4 |
A000377 | Expansion of f(-q^3) * f(-q^8) * chi(-q^12) / chi(-q) in powers of q where chi(), f() are Ramanujan theta functions. | [
"1",
"1",
"1",
"1",
"1",
"2",
"1",
"2",
"1",
"1",
"2",
"2",
"1",
"0",
"2",
"2",
"1",
"0",
"1",
"0",
"2",
"2",
"2",
"0",
"1",
"3",
"0",
"1",
"2",
"2",
"2",
"2",
"1",
"2",
"0",
"4",
"1",
"0",
"0",
"0",
"2",
"0",
"2",
"0",
"2",
"... | [
"nonn",
"easy",
"nice",
"mult"
] | 68 | 0 | 6 | [
"A000377",
"A129402",
"A190611"
] | null | N. J. A. Sloane | 2025-08-05T10:34:02 | oeisdata/seq/A000/A000377.seq | b1e8f87842b453463e6e894671e3ac9d |
A000378 | Sums of three squares: numbers of the form x^2 + y^2 + z^2. | [
"0",
"1",
"2",
"3",
"4",
"5",
"6",
"8",
"9",
"10",
"11",
"12",
"13",
"14",
"16",
"17",
"18",
"19",
"20",
"21",
"22",
"24",
"25",
"26",
"27",
"29",
"30",
"32",
"33",
"34",
"35",
"36",
"37",
"38",
"40",
"41",
"42",
"43",
"44",
"45",
"46",... | [
"nonn"
] | 131 | 1 | 3 | [
"A000164",
"A000290",
"A000378",
"A000404",
"A000408",
"A000415",
"A000419",
"A001481",
"A002828",
"A004215",
"A005875",
"A034043",
"A034044",
"A034045",
"A034046",
"A034047",
"A047449",
"A065883",
"A071374",
"A072400",
"A072401",
"A125084"
] | null | N. J. A. Sloane | 2025-11-12T11:13:31 | oeisdata/seq/A000/A000378.seq | fa736eb66f485a87a3c9c9f82410d87e |
A000379 | Numbers where total number of 1-bits in the exponents of their prime factorization is even; a 2-way classification of integers: complement of A000028. | [
"1",
"6",
"8",
"10",
"12",
"14",
"15",
"18",
"20",
"21",
"22",
"26",
"27",
"28",
"32",
"33",
"34",
"35",
"36",
"38",
"39",
"44",
"45",
"46",
"48",
"50",
"51",
"52",
"55",
"57",
"58",
"62",
"63",
"64",
"65",
"68",
"69",
"74",
"75",
"76",
... | [
"nonn",
"easy",
"nice"
] | 77 | 1 | 2 | [
"A000028",
"A000069",
"A000120",
"A000201",
"A000379",
"A001950",
"A001969",
"A010060",
"A030229",
"A030231",
"A037445",
"A050376",
"A059897",
"A064179",
"A064547",
"A092248",
"A123240",
"A124010",
"A131181",
"A133008",
"A238748",
"A262675",
"A268386",
"A268387",
"A26... | [
"M4065",
"N1685"
] | N. J. A. Sloane | 2025-09-11T21:45:31 | oeisdata/seq/A000/A000379.seq | 04666cd9f2bd54a8f1c61baaf8b14b0d |
A000380 | Number of permutations of an n-sequence discordant with three given permutations (see reference) in n-3 places. | [
"6",
"8",
"40",
"176",
"1421",
"10352",
"93114",
"912920",
"9929997",
"117970704",
"1521176826",
"21150414880",
"315400444070",
"5020920314016",
"84979755347122",
"1523710321272384",
"28851091193764023",
"575253584489378040",
"12047084261153160394",
"264377395040950523112",
"... | [
"nonn"
] | 24 | 3 | 1 | [
"A000380",
"A000388",
"A000440",
"A000470",
"A000476",
"A000492",
"A000500"
] | [
"M4071",
"N1686"
] | N. J. A. Sloane | 2015-06-28T10:30:05 | oeisdata/seq/A000/A000380.seq | 58ec2f6d66e4bb50ff7a1c300f8e00d6 |
A000381 | Essentially the same as A001611. | [
"2",
"3",
"4",
"6",
"9",
"14",
"22",
"35",
"56",
"90",
"145",
"234",
"378",
"611",
"988",
"1598",
"2585",
"4182",
"6766"
] | [
"dead"
] | 34 | 0 | 1 | [
"A000381",
"A001611"
] | [
"M0574",
"N0208"
] | N. J. A. Sloane, Apr 17 2015 | 2023-08-06T01:12:01 | oeisdata/seq/A000/A000381.seq | cb5c5290a5ce67d40079c8b8a5650e4f |
A000382 | Restricted permutations. | [
"6",
"11",
"20",
"36",
"65",
"119",
"218",
"400",
"735",
"1351",
"2484",
"4568",
"8401",
"15451",
"28418",
"52268",
"96135",
"176819",
"325220",
"598172",
"1100209",
"2023599",
"3721978",
"6845784",
"12591359",
"23159119",
"42596260",
"78346736",
"144102113",
... | [
"nonn",
"easy"
] | 41 | 4 | 1 | [
"A000382",
"A000496",
"A008305",
"A020992"
] | [
"M4087",
"N1696"
] | N. J. A. Sloane | 2022-04-13T13:25:14 | oeisdata/seq/A000/A000382.seq | 05296e9f9226da033ac454ca7f81a6fe |
A000383 | Hexanacci numbers with a(0) = ... = a(5) = 1. | [
"1",
"1",
"1",
"1",
"1",
"1",
"6",
"11",
"21",
"41",
"81",
"161",
"321",
"636",
"1261",
"2501",
"4961",
"9841",
"19521",
"38721",
"76806",
"152351",
"302201",
"599441",
"1189041",
"2358561",
"4678401",
"9279996",
"18407641",
"36513081",
"72426721",
"1436... | [
"nonn",
"easy"
] | 67 | 0 | 7 | [
"A000383",
"A001592",
"A060455",
"A247192",
"A249413"
] | [
"M4088",
"N1697"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000383.seq | 3f9504c81e8e382dfa381afbfe5631f4 |
A000384 | Hexagonal numbers: a(n) = n*(2*n-1). | [
"0",
"1",
"6",
"15",
"28",
"45",
"66",
"91",
"120",
"153",
"190",
"231",
"276",
"325",
"378",
"435",
"496",
"561",
"630",
"703",
"780",
"861",
"946",
"1035",
"1128",
"1225",
"1326",
"1431",
"1540",
"1653",
"1770",
"1891",
"2016",
"2145",
"2278",
... | [
"nonn",
"easy",
"nice"
] | 507 | 0 | 3 | [
"A000217",
"A000384",
"A001844",
"A002939",
"A005408",
"A014105",
"A027907",
"A046092",
"A093561",
"A100345",
"A127672",
"A280851"
] | [
"M4108",
"N1705"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000384.seq | 1e7bd17addace4f8966669c24d250b8b |
A000385 | Convolution of A000203 with itself. | [
"1",
"6",
"17",
"38",
"70",
"116",
"185",
"258",
"384",
"490",
"686",
"826",
"1124",
"1292",
"1705",
"1896",
"2491",
"2670",
"3416",
"3680",
"4602",
"4796",
"6110",
"6178",
"7700",
"7980",
"9684",
"9730",
"12156",
"11920",
"14601",
"14752",
"17514",
... | [
"nonn",
"easy",
"look",
"changed"
] | 75 | 1 | 2 | [
"A000203",
"A000385",
"A001158",
"A024916",
"A319083",
"A340793"
] | [
"M4113",
"N1708"
] | N. J. A. Sloane | 2026-01-15T10:22:16 | oeisdata/seq/A000/A000385.seq | 6b3c35efdf40758d26c3717afc4c1bd7 |
A000386 | Coefficients of ménage hit polynomials. | [
"0",
"0",
"0",
"1",
"6",
"20",
"134",
"915",
"7324",
"65784",
"657180",
"7223637",
"86637650",
"1125842556",
"15757002706",
"236298742375",
"3780061394232",
"64251145312880",
"1156374220457784",
"21968796934412649",
"439337048505773790",
"9225384943965382564",
"2029454182... | [
"nonn"
] | 21 | 0 | 5 | [
"A000386",
"A058057"
] | [
"M4137",
"N1715"
] | N. J. A. Sloane | 2022-02-01T00:55:27 | oeisdata/seq/A000/A000386.seq | 4726c196f5635c62f401f33fd5993a16 |
A000387 | Rencontres numbers: number of permutations of [n] with exactly two fixed points. | [
"0",
"0",
"1",
"0",
"6",
"20",
"135",
"924",
"7420",
"66744",
"667485",
"7342280",
"88107426",
"1145396460",
"16035550531",
"240533257860",
"3848532125880",
"65425046139824",
"1177650830516985",
"22375365779822544",
"447507315596451070",
"9397653627525472260",
"2067483798... | [
"nonn",
"easy",
"changed"
] | 115 | 0 | 5 | [
"A000387",
"A003221",
"A008290",
"A008291",
"A170942"
] | [
"M4138",
"N1716"
] | N. J. A. Sloane | 2026-01-15T10:22:24 | oeisdata/seq/A000/A000387.seq | 72ea922d99bc52c5e313446eb1fd0058 |
A000388 | Number of permutations of an n-sequence discordant with three given permutations (see reference) in n-2 places. | [
"6",
"20",
"180",
"1106",
"9292",
"82980",
"831545",
"9139482",
"109595496",
"1423490744",
"19911182207",
"298408841160",
"4770598226296",
"81037124739588",
"1457607971046492",
"27675791180024802",
"553166885187641670",
"11609691036091870428",
"255273744004170486155",
"58683089... | [
"nonn"
] | 28 | 4 | 1 | [
"A000380",
"A000388",
"A000440",
"A000470",
"A000476",
"A000492",
"A000500"
] | [
"M4139",
"N1717"
] | N. J. A. Sloane | 2015-06-28T10:29:39 | oeisdata/seq/A000/A000388.seq | db741cda3c525d1e10b55b20007e187c |
A000389 | Binomial coefficients C(n,5). | [
"0",
"0",
"0",
"0",
"0",
"1",
"6",
"21",
"56",
"126",
"252",
"462",
"792",
"1287",
"2002",
"3003",
"4368",
"6188",
"8568",
"11628",
"15504",
"20349",
"26334",
"33649",
"42504",
"53130",
"65780",
"80730",
"98280",
"118755",
"142506",
"169911",
"201376",... | [
"nonn",
"easy",
"nice",
"changed"
] | 267 | 0 | 7 | [
"A000217",
"A000292",
"A000332",
"A000389",
"A000579",
"A000580",
"A000581",
"A000582",
"A001477",
"A002299",
"A005583",
"A049310",
"A051747",
"A052787",
"A053127",
"A063843",
"A067764",
"A099242",
"A104712",
"A110555",
"A128767",
"A132366",
"A234249",
"A242023",
"A27... | [
"M4142",
"N1719"
] | N. J. A. Sloane | 2026-01-12T08:41:02 | oeisdata/seq/A000/A000389.seq | 89f9d11dee05a880fbdd02cb2b8c1ac5 |
A000390 | Number of 5-dimensional partitions of n. | [
"1",
"6",
"21",
"71",
"216",
"657",
"1907",
"5507",
"15522",
"43352",
"119140",
"323946",
"869476",
"2308071",
"6056581",
"15724170",
"40393693",
"102736274",
"258790004",
"645968054",
"1598460229",
"3923114261",
"9554122089",
"23098084695",
"55458417125",
"13229394... | [
"nonn"
] | 51 | 1 | 2 | [
"A000012",
"A000041",
"A000219",
"A000293",
"A000334",
"A000390",
"A000416",
"A096751"
] | [
"M4143",
"N1720"
] | N. J. A. Sloane | 2025-11-05T15:21:39 | oeisdata/seq/A000/A000390.seq | 70f91447db03e8a8d4f636548f7bd504 |
A000391 | Euler transform of A000332. | [
"1",
"6",
"21",
"71",
"216",
"672",
"1982",
"5817",
"16582",
"46633",
"128704",
"350665",
"941715",
"2499640",
"6557378",
"17024095",
"43756166",
"111433472",
"281303882",
"704320180",
"1749727370",
"4314842893",
"10565857064",
"25700414815",
"62115621317",
"1492145... | [
"nonn"
] | 43 | 1 | 2 | [
"A000041",
"A000219",
"A000294",
"A000335",
"A000391",
"A000417",
"A000428",
"A255965"
] | [
"M4144",
"N1721"
] | N. J. A. Sloane | 2025-11-05T15:21:39 | oeisdata/seq/A000/A000391.seq | 0f685254aff6dca331a4c3b2f66477b4 |
A000392 | Stirling numbers of second kind S(n,3). | [
"0",
"0",
"0",
"1",
"6",
"25",
"90",
"301",
"966",
"3025",
"9330",
"28501",
"86526",
"261625",
"788970",
"2375101",
"7141686",
"21457825",
"64439010",
"193448101",
"580606446",
"1742343625",
"5228079450",
"15686335501",
"47063200806",
"141197991025",
"423610750290... | [
"nonn",
"nice",
"easy"
] | 220 | 0 | 5 | [
"A000225",
"A000392",
"A002275",
"A002452",
"A003462",
"A003463",
"A003464",
"A007051",
"A008277",
"A016123",
"A016125",
"A016256",
"A023000",
"A023001",
"A028243",
"A056509",
"A122554"
] | [
"M4167",
"N1734"
] | N. J. A. Sloane | 2025-11-26T15:59:31 | oeisdata/seq/A000/A000392.seq | b2f5edc1d788d5e206a09ac40ca59fdc |
A000393 | Number of n-node rooted trees of height 6. | [
"0",
"0",
"0",
"0",
"0",
"0",
"1",
"6",
"26",
"94",
"308",
"941",
"2744",
"7722",
"21166",
"56809",
"149971",
"390517",
"1005491",
"2564164",
"6485901",
"16289602",
"40659669",
"100934017",
"249343899",
"613286048",
"1502515487",
"3667953650",
"8925161513",
... | [
"nonn"
] | 29 | 1 | 8 | [
"A000393",
"A034781"
] | [
"M4170",
"N1736"
] | N. J. A. Sloane | 2017-07-08T01:25:12 | oeisdata/seq/A000/A000393.seq | 5ce7b4ae44b46d19cceb4d2496f909c8 |
A000394 | Numbers of form x^2 + y^2 + 7z^2. | [
"0",
"1",
"2",
"4",
"5",
"7",
"8",
"9",
"10",
"11",
"12",
"13",
"15",
"16",
"17",
"18",
"20",
"23",
"24",
"25",
"26",
"27",
"28",
"29",
"30",
"32",
"33",
"34",
"36",
"37",
"38",
"39",
"40",
"41",
"43",
"44",
"45",
"46",
"47",
"48",
"49"... | [
"nonn"
] | 16 | 0 | 3 | [
"A000394",
"A097633"
] | null | N. J. A. Sloane | 2017-07-08T01:24:35 | oeisdata/seq/A000/A000394.seq | d1114ad31507a2cbbab6d55a9750eec4 |
A000395 | 6th power of rooted tree enumerator; number of linear forests of 6 rooted trees. | [
"1",
"6",
"27",
"104",
"369",
"1236",
"3989",
"12522",
"38535",
"116808",
"350064",
"1039896",
"3068145",
"9004182",
"26314773",
"76652582",
"222705603",
"645731148",
"1869303857",
"5404655358",
"15611296146",
"45060069406",
"129989169909",
"374843799786",
"1080624405... | [
"nonn"
] | 37 | 6 | 2 | [
"A000081",
"A000106",
"A000242",
"A000300",
"A000343",
"A000395",
"A339067"
] | [
"M4175",
"N1739"
] | N. J. A. Sloane | 2021-01-03T04:31:33 | oeisdata/seq/A000/A000395.seq | 2819e8e7d13eee6776f53da70e629b60 |
A000396 | Perfect numbers k: k is equal to the sum of the proper divisors of k. | [
"6",
"28",
"496",
"8128",
"33550336",
"8589869056",
"137438691328",
"2305843008139952128",
"2658455991569831744654692615953842176",
"191561942608236107294793378084303638130997321548169216",
"13164036458569648337239753460458722910223472318386943117783728128"
] | [
"nonn",
"nice",
"core"
] | 535 | 1 | 1 | [
"A000043",
"A000217",
"A000384",
"A000396",
"A000668",
"A001065",
"A005153",
"A005820",
"A005835",
"A006039",
"A006516",
"A007539",
"A007593",
"A007691",
"A019279",
"A023196",
"A027687",
"A028499",
"A028502",
"A033879",
"A033880",
"A034916",
"A043305",
"A046060",
"A04... | [
"M4186",
"N1744"
] | N. J. A. Sloane | 2026-01-03T11:22:21 | oeisdata/seq/A000/A000396.seq | 150bb20bef10a9f0f235f7cc7de8360c |
A000397 | Number of partitions into non-integral powers. | [
"6",
"32",
"109",
"288",
"654",
"1337",
"2506",
"4414",
"7379",
"11822",
"18273",
"27356",
"39938",
"56974",
"79607",
"109267",
"147523",
"196295",
"257715",
"334407",
"429086",
"545034",
"685917",
"855886",
"1059360",
"1301776",
"1588321",
"1925620",
"2320544... | [
"nonn"
] | 27 | 5 | 1 | null | [
"M4212",
"N1757"
] | N. J. A. Sloane | 2024-07-30T02:50:12 | oeisdata/seq/A000/A000397.seq | f9d47ee02185195b67fae3e405c1bc3e |
A000398 | Numbers of form x^2 + 2y^2 + 2yz + 4z^2. | [
"0",
"1",
"2",
"3",
"4",
"5",
"6",
"8",
"9",
"11",
"12",
"13",
"14",
"15",
"16",
"17",
"18",
"19",
"20",
"22",
"23",
"24",
"25",
"26",
"27",
"28",
"29",
"30",
"31",
"32",
"33",
"34",
"36",
"37",
"38",
"39",
"40",
"41",
"43",
"44",
"45",... | [
"nonn",
"easy"
] | 21 | 1 | 3 | [
"A000398",
"A097634"
] | null | N. J. A. Sloane | 2017-07-08T01:23:21 | oeisdata/seq/A000/A000398.seq | f428eabc4a097d917fe20897d0e3e928 |
A000399 | Unsigned Stirling numbers of first kind s(n,3). | [
"1",
"6",
"35",
"225",
"1624",
"13132",
"118124",
"1172700",
"12753576",
"150917976",
"1931559552",
"26596717056",
"392156797824",
"6165817614720",
"102992244837120",
"1821602444624640",
"34012249593822720",
"668609730341153280",
"13803759753640704000"
] | [
"nonn",
"easy",
"nice"
] | 101 | 3 | 2 | [
"A000254",
"A000399",
"A000454",
"A000482",
"A001233",
"A001234",
"A008275",
"A243569",
"A243570"
] | [
"M4218",
"N1762"
] | N. J. A. Sloane | 2025-11-18T17:05:08 | oeisdata/seq/A000/A000399.seq | 5beec562e4266ac32cc65d3da25ec58c |
A000400 | Powers of 6: a(n) = 6^n. | [
"1",
"6",
"36",
"216",
"1296",
"7776",
"46656",
"279936",
"1679616",
"10077696",
"60466176",
"362797056",
"2176782336",
"13060694016",
"78364164096",
"470184984576",
"2821109907456",
"16926659444736",
"101559956668416",
"609359740010496",
"3656158440062976",
"21936950640377... | [
"easy",
"nonn"
] | 151 | 0 | 2 | [
"A000005",
"A000290",
"A000400",
"A003992",
"A011577",
"A036561",
"A159991",
"A169604",
"A225816",
"A329332"
] | [
"M4224",
"N1765"
] | N. J. A. Sloane | 2025-03-09T12:43:44 | oeisdata/seq/A000/A000400.seq | 7f2b15db3a157d70d37d56cdfdb07d0e |
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