fact
stringlengths
6
3.84k
type
stringclasses
11 values
library
stringclasses
32 values
imports
listlengths
1
14
filename
stringlengths
20
95
symbolic_name
stringlengths
1
90
docstring
stringlengths
7
20k
addWellApproximable_ae_empty_or_univ (δ : ℕ → ℝ) (hδ : Tendsto δ atTop (𝓝 0)) : (∀ᵐ x, ¬addWellApproximable 𝕊 δ x) ∨ ∀ᵐ x, addWellApproximable 𝕊 δ x := by /- Sketch of proof: Let `E := addWellApproximable 𝕊 δ`. For each prime `p : ℕ`, we can partition `E` into three pieces `E = (A p) ∪ (B p) ∪ (C p)` ...
theorem
NumberTheory
[ "Mathlib.Dynamics.Ergodic.AddCircle", "Mathlib.MeasureTheory.Covering.LiminfLimsup" ]
Mathlib/NumberTheory/WellApproximable.lean
addWellApproximable_ae_empty_or_univ
**Gallagher's ergodic theorem** on Diophantine approximation.
_root_.NormedAddCommGroup.exists_norm_nsmul_le {A : Type*} [NormedAddCommGroup A] [CompactSpace A] [PreconnectedSpace A] [MeasurableSpace A] [BorelSpace A] {μ : Measure A} [μ.IsAddHaarMeasure] (ξ : A) {n : ℕ} (hn : 0 < n) (δ : ℝ) (hδ : μ univ ≤ (n + 1) • μ (closedBall (0 : A) (δ / 2))) : ∃ j ∈ Icc 1 n, ...
lemma
NumberTheory
[ "Mathlib.Dynamics.Ergodic.AddCircle", "Mathlib.MeasureTheory.Covering.LiminfLimsup" ]
Mathlib/NumberTheory/WellApproximable.lean
_root_.NormedAddCommGroup.exists_norm_nsmul_le
A general version of **Dirichlet's approximation theorem**. See also `AddCircle.exists_norm_nsmul_le`.
exists_norm_nsmul_le (ξ : 𝕊) {n : ℕ} (hn : 0 < n) : ∃ j ∈ Icc 1 n, ‖j • ξ‖ ≤ T / ↑(n + 1) := by apply NormedAddCommGroup.exists_norm_nsmul_le (μ := volume) ξ hn rw [AddCircle.measure_univ, volume_closedBall, ← ENNReal.ofReal_nsmul, mul_div_cancel₀ _ two_ne_zero, min_eq_right (div_le_self hT.out.le <| by si...
lemma
NumberTheory
[ "Mathlib.Dynamics.Ergodic.AddCircle", "Mathlib.MeasureTheory.Covering.LiminfLimsup" ]
Mathlib/NumberTheory/WellApproximable.lean
exists_norm_nsmul_le
**Dirichlet's approximation theorem** See also `Real.exists_rat_abs_sub_le_and_den_le`.
@[simp] wilsons_lemma : ((p - 1)! : ZMod p) = -1 := by refine calc ((p - 1)! : ZMod p) = ∏ x ∈ Ico 1 (succ (p - 1)), (x : ZMod p) := by rw [← Finset.prod_Ico_id_eq_factorial, prod_natCast] _ = ∏ x : (ZMod p)ˣ, (x : ZMod p) := ?_ _ = -1 := by simp_rw [← Units.coeHom_apply, ← map_p...
theorem
NumberTheory
[ "Mathlib.FieldTheory.Finite.Basic" ]
Mathlib/NumberTheory/Wilson.lean
wilsons_lemma
**Wilson's Lemma**: the product of `1`, ..., `p-1` is `-1` modulo `p`.
prod_Ico_one_prime : ∏ x ∈ Ico 1 p, (x : ZMod p) = -1 := by conv => congr congr rw [← Nat.add_one_sub_one p, succ_sub (Fact.out (p := p.Prime)).pos] rw [← prod_natCast, Finset.prod_Ico_id_eq_factorial, wilsons_lemma]
theorem
NumberTheory
[ "Mathlib.FieldTheory.Finite.Basic" ]
Mathlib/NumberTheory/Wilson.lean
prod_Ico_one_prime
null
prime_of_fac_equiv_neg_one (h : ((n - 1)! : ZMod n) = -1) (h1 : n ≠ 1) : Prime n := by rcases eq_or_ne n 0 with (rfl | h0) · norm_num at h replace h1 : 1 < n := n.two_le_iff.mpr ⟨h0, h1⟩ by_contra h2 obtain ⟨m, hm1, hm2 : 1 < m, hm3⟩ := exists_dvd_of_not_prime2 h1 h2 have hm : m ∣ (n - 1)! := Nat.dvd_factor...
theorem
NumberTheory
[ "Mathlib.FieldTheory.Finite.Basic" ]
Mathlib/NumberTheory/Wilson.lean
prime_of_fac_equiv_neg_one
For `n ≠ 1`, `(n-1)!` is congruent to `-1` modulo `n` only if n is prime.
prime_iff_fac_equiv_neg_one (h : n ≠ 1) : Prime n ↔ ((n - 1)! : ZMod n) = -1 := by refine ⟨fun h1 => ?_, fun h2 => prime_of_fac_equiv_neg_one h2 h⟩ haveI := Fact.mk h1 exact ZMod.wilsons_lemma n
theorem
NumberTheory
[ "Mathlib.FieldTheory.Finite.Basic" ]
Mathlib/NumberTheory/Wilson.lean
prime_iff_fac_equiv_neg_one
**Wilson's Theorem**: For `n ≠ 1`, `(n-1)!` is congruent to `-1` modulo `n` iff n is prime.
bernoulliFun (k : ℕ) (x : ℝ) : ℝ := (Polynomial.map (algebraMap ℚ ℝ) (Polynomial.bernoulli k)).eval x
def
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFun
The function `x ↦ Bₖ(x) : ℝ → ℝ`.
bernoulliFun_eval_zero (k : ℕ) : bernoulliFun k 0 = bernoulli k := by rw [bernoulliFun, Polynomial.eval_zero_map, Polynomial.bernoulli_eval_zero, eq_ratCast]
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFun_eval_zero
null
bernoulliFun_endpoints_eq_of_ne_one {k : ℕ} (hk : k ≠ 1) : bernoulliFun k 1 = bernoulliFun k 0 := by rw [bernoulliFun_eval_zero, bernoulliFun, Polynomial.eval_one_map, Polynomial.bernoulli_eval_one, bernoulli_eq_bernoulli'_of_ne_one hk, eq_ratCast]
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFun_endpoints_eq_of_ne_one
null
bernoulliFun_eval_one (k : ℕ) : bernoulliFun k 1 = bernoulliFun k 0 + ite (k = 1) 1 0 := by rw [bernoulliFun, bernoulliFun_eval_zero, Polynomial.eval_one_map, Polynomial.bernoulli_eval_one] split_ifs with h · rw [h, bernoulli_one, bernoulli'_one, eq_ratCast] push_cast; ring · rw [bernoulli_eq_bernoulli'_of_...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFun_eval_one
null
hasDerivAt_bernoulliFun (k : ℕ) (x : ℝ) : HasDerivAt (bernoulliFun k) (k * bernoulliFun (k - 1) x) x := by convert ((Polynomial.bernoulli k).map <| algebraMap ℚ ℝ).hasDerivAt x using 1 simp only [bernoulliFun, Polynomial.derivative_map, Polynomial.derivative_bernoulli k, Polynomial.map_mul, Polynomial.map_n...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasDerivAt_bernoulliFun
null
antideriv_bernoulliFun (k : ℕ) (x : ℝ) : HasDerivAt (fun x => bernoulliFun (k + 1) x / (k + 1)) (bernoulliFun k x) x := by convert (hasDerivAt_bernoulliFun (k + 1) x).div_const _ using 1 simp [Nat.cast_add_one_ne_zero k]
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
antideriv_bernoulliFun
null
integral_bernoulliFun_eq_zero {k : ℕ} (hk : k ≠ 0) : ∫ x : ℝ in 0..1, bernoulliFun k x = 0 := by rw [integral_eq_sub_of_hasDerivAt (fun x _ => antideriv_bernoulliFun k x) ((Polynomial.continuous _).intervalIntegrable _ _)] rw [bernoulliFun_eval_one] split_ifs with h · exfalso; exact hk (Nat.succ_inj.m...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
integral_bernoulliFun_eq_zero
null
bernoulliFourierCoeff (k : ℕ) (n : ℤ) : ℂ := fourierCoeffOn zero_lt_one (fun x => bernoulliFun k x) n
def
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFourierCoeff
The `n`-th Fourier coefficient of the `k`-th Bernoulli function on the interval `[0, 1]`.
bernoulliFourierCoeff_recurrence (k : ℕ) {n : ℤ} (hn : n ≠ 0) : bernoulliFourierCoeff k n = 1 / (-2 * π * I * n) * (ite (k = 1) 1 0 - k * bernoulliFourierCoeff (k - 1) n) := by unfold bernoulliFourierCoeff rw [fourierCoeffOn_of_hasDerivAt zero_lt_one hn (fun x _ => (hasDerivAt_bernoulliFun k x).ofRe...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFourierCoeff_recurrence
Recurrence relation (in `k`) for the `n`-th Fourier coefficient of `Bₖ`.
bernoulli_zero_fourier_coeff {n : ℤ} (hn : n ≠ 0) : bernoulliFourierCoeff 0 n = 0 := by simpa using bernoulliFourierCoeff_recurrence 0 hn
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulli_zero_fourier_coeff
The Fourier coefficients of `B₀(x) = 1`.
bernoulliFourierCoeff_zero {k : ℕ} (hk : k ≠ 0) : bernoulliFourierCoeff k 0 = 0 := by simp_rw [bernoulliFourierCoeff, fourierCoeffOn_eq_integral, neg_zero, fourier_zero, sub_zero, div_one, one_smul, intervalIntegral.integral_ofReal, integral_bernoulliFun_eq_zero hk, ofReal_zero]
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFourierCoeff_zero
The `0`-th Fourier coefficient of `Bₖ(x)`.
bernoulliFourierCoeff_eq {k : ℕ} (hk : k ≠ 0) (n : ℤ) : bernoulliFourierCoeff k n = -k ! / (2 * π * I * n) ^ k := by rcases eq_or_ne n 0 with (rfl | hn) · rw [bernoulliFourierCoeff_zero hk, Int.cast_zero, mul_zero, zero_pow hk, div_zero] refine Nat.le_induction ?_ (fun k hk h'k => ?_) k (Nat.one_le_iff_...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
bernoulliFourierCoeff_eq
null
periodizedBernoulli (k : ℕ) : 𝕌 → ℝ := AddCircle.liftIco 1 0 (bernoulliFun k)
def
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
periodizedBernoulli
The Bernoulli polynomial, extended from `[0, 1)` to the unit circle.
periodizedBernoulli.continuous {k : ℕ} (hk : k ≠ 1) : Continuous (periodizedBernoulli k) := AddCircle.liftIco_zero_continuous (mod_cast (bernoulliFun_endpoints_eq_of_ne_one hk).symm) (Polynomial.continuous _).continuousOn
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
periodizedBernoulli.continuous
null
fourierCoeff_bernoulli_eq {k : ℕ} (hk : k ≠ 0) (n : ℤ) : fourierCoeff ((↑) ∘ periodizedBernoulli k : 𝕌 → ℂ) n = -k ! / (2 * π * I * n) ^ k := by have : ((↑) ∘ periodizedBernoulli k : 𝕌 → ℂ) = AddCircle.liftIco 1 0 ((↑) ∘ bernoulliFun k) := by ext1 x; rfl rw [this, fourierCoeff_liftIco_eq] simpa only [ze...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
fourierCoeff_bernoulli_eq
null
summable_bernoulli_fourier {k : ℕ} (hk : 2 ≤ k) : Summable (fun n => -k ! / (2 * π * I * n) ^ k : ℤ → ℂ) := by have : ∀ n : ℤ, -(k ! : ℂ) / (2 * π * I * n) ^ k = -k ! / (2 * π * I) ^ k * (1 / (n : ℂ) ^ k) := by intro n; rw [mul_one_div, div_div, ← mul_pow] simp_rw [this] refine Summable.mul_left _ <...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
summable_bernoulli_fourier
null
hasSum_one_div_pow_mul_fourier_mul_bernoulliFun {k : ℕ} (hk : 2 ≤ k) {x : ℝ} (hx : x ∈ Icc (0 : ℝ) 1) : HasSum (fun n : ℤ => 1 / (n : ℂ) ^ k * fourier n (x : 𝕌)) (-(2 * π * I) ^ k / k ! * bernoulliFun k x) := by suffices ∀ {y : ℝ}, y ∈ Ico (0 : ℝ) 1 → HasSum (fun (n : ℤ) ↦ 1 / (n : ℂ) ^ k * fouri...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_one_div_pow_mul_fourier_mul_bernoulliFun
null
hasSum_one_div_nat_pow_mul_fourier {k : ℕ} (hk : 2 ≤ k) {x : ℝ} (hx : x ∈ Icc (0 : ℝ) 1) : HasSum (fun n : ℕ => (1 : ℂ) / (n : ℂ) ^ k * (fourier n (x : 𝕌) + (-1 : ℂ) ^ k * fourier (-n) (x : 𝕌))) (-(2 * π * I) ^ k / k ! * bernoulliFun k x) := by convert (hasSum_one_div_pow_mul_fourier_mul_ber...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_one_div_nat_pow_mul_fourier
null
hasSum_one_div_nat_pow_mul_cos {k : ℕ} (hk : k ≠ 0) {x : ℝ} (hx : x ∈ Icc (0 : ℝ) 1) : HasSum (fun n : ℕ => 1 / (n : ℝ) ^ (2 * k) * Real.cos (2 * π * n * x)) ((-1 : ℝ) ^ (k + 1) * (2 * π) ^ (2 * k) / 2 / (2 * k)! * (Polynomial.map (algebraMap ℚ ℝ) (Polynomial.bernoulli (2 * k))).eval x) := by have :...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_one_div_nat_pow_mul_cos
null
hasSum_one_div_nat_pow_mul_sin {k : ℕ} (hk : k ≠ 0) {x : ℝ} (hx : x ∈ Icc (0 : ℝ) 1) : HasSum (fun n : ℕ => 1 / (n : ℝ) ^ (2 * k + 1) * Real.sin (2 * π * n * x)) ((-1 : ℝ) ^ (k + 1) * (2 * π) ^ (2 * k + 1) / 2 / (2 * k + 1)! * (Polynomial.map (algebraMap ℚ ℝ) (Polynomial.bernoulli (2 * k + 1))).eval x...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_one_div_nat_pow_mul_sin
null
hasSum_zeta_nat {k : ℕ} (hk : k ≠ 0) : HasSum (fun n : ℕ => 1 / (n : ℝ) ^ (2 * k)) ((-1 : ℝ) ^ (k + 1) * (2 : ℝ) ^ (2 * k - 1) * π ^ (2 * k) * bernoulli (2 * k) / (2 * k)!) := by convert hasSum_one_div_nat_pow_mul_cos hk (left_mem_Icc.mpr zero_le_one) using 1 · ext1 n; rw [mul_zero, Real.cos_zero,...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_zeta_nat
null
hasSum_zeta_two : HasSum (fun n : ℕ => (1 : ℝ) / (n : ℝ) ^ 2) (π ^ 2 / 6) := by convert hasSum_zeta_nat one_ne_zero using 1; rw [mul_one] rw [bernoulli_eq_bernoulli'_of_ne_one (by decide : 2 ≠ 1), bernoulli'_two] norm_num [Nat.factorial]; field_simp
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_zeta_two
null
hasSum_zeta_four : HasSum (fun n : ℕ => (1 : ℝ) / (n : ℝ) ^ 4) (π ^ 4 / 90) := by convert hasSum_zeta_nat two_ne_zero using 1; norm_num rw [bernoulli_eq_bernoulli'_of_ne_one, bernoulli'_four] · norm_num [Nat.factorial]; field_simp; ring · decide
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_zeta_four
null
Polynomial.bernoulli_three_eval_one_quarter : (Polynomial.bernoulli 3).eval (1 / 4) = 3 / 64 := by simp_rw [Polynomial.bernoulli, Finset.sum_range_succ, Polynomial.eval_add, Polynomial.eval_monomial] rw [Finset.sum_range_zero, Polynomial.eval_zero, zero_add, bernoulli_one] rw [bernoulli_eq_bernoulli'_of_n...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
Polynomial.bernoulli_three_eval_one_quarter
null
hasSum_L_function_mod_four_eval_three : HasSum (fun n : ℕ => (1 : ℝ) / (n : ℝ) ^ 3 * Real.sin (π * n / 2)) (π ^ 3 / 32) := by apply (congr_arg₂ HasSum ?_ ?_).to_iff.mp <| hasSum_one_div_nat_pow_mul_sin one_ne_zero (?_ : 1 / 4 ∈ Icc (0 : ℝ) 1) · ext1 n norm_num left congr 1 ring · have : (1...
theorem
NumberTheory
[ "Mathlib.NumberTheory.BernoulliPolynomials", "Mathlib.MeasureTheory.Integral.IntervalIntegral.Basic", "Mathlib.Analysis.Calculus.Deriv.Polynomial", "Mathlib.Analysis.Fourier.AddCircle", "Mathlib.Analysis.PSeries" ]
Mathlib/NumberTheory/ZetaValues.lean
hasSum_L_function_mod_four_eval_three
Explicit formula for `L(χ, 3)`, where `χ` is the unique nontrivial Dirichlet character modulo 4.
protected Symmetric.compl (h : Symmetric r) : Symmetric rᶜ := fun _ _ hr hr' => hr <| h hr'
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
Symmetric.compl
null
IsAntichain (r : α → α → Prop) (s : Set α) : Prop := s.Pairwise rᶜ
def
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain
An antichain is a set such that no two distinct elements are related.
@[simp] protected empty : IsAntichain r ∅ := pairwise_empty _ @[simp] protected theorem singleton : IsAntichain r {a} := pairwise_singleton _ _
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
empty
null
protected subset (hs : IsAntichain r s) (h : t ⊆ s) : IsAntichain r t := hs.mono h
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
subset
null
mono (hs : IsAntichain r₁ s) (h : r₂ ≤ r₁) : IsAntichain r₂ s := hs.mono' <| compl_le_compl h
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
mono
null
mono_on (hs : IsAntichain r₁ s) (h : s.Pairwise fun ⦃a b⦄ => r₂ a b → r₁ a b) : IsAntichain r₂ s := hs.imp_on <| h.imp fun _ _ h h₁ h₂ => h₁ <| h h₂
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
mono_on
null
protected eq (hs : IsAntichain r s) {a b : α} (ha : a ∈ s) (hb : b ∈ s) (h : r a b) : a = b := Set.Pairwise.eq hs ha hb <| not_not_intro h
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
eq
null
protected eq' (hs : IsAntichain r s) {a b : α} (ha : a ∈ s) (hb : b ∈ s) (h : r b a) : a = b := (hs.eq hb ha h).symm
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
eq'
null
protected isAntisymm (h : IsAntichain r univ) : IsAntisymm α r := ⟨fun _ _ ha _ => h.eq trivial trivial ha⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isAntisymm
null
protected subsingleton [IsTrichotomous α r] (h : IsAntichain r s) : s.Subsingleton := by rintro a ha b hb obtain hab | hab | hab := trichotomous_of r a b · exact h.eq ha hb hab · exact hab · exact h.eq' ha hb hab
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
subsingleton
null
protected flip (hs : IsAntichain r s) : IsAntichain (flip r) s := fun _ ha _ hb h => hs hb ha h.symm
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
flip
null
swap (hs : IsAntichain r s) : IsAntichain (swap r) s := hs.flip
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
swap
null
image (hs : IsAntichain r s) (f : α → β) (h : ∀ ⦃a b⦄, r' (f a) (f b) → r a b) : IsAntichain r' (f '' s) := by rintro _ ⟨b, hb, rfl⟩ _ ⟨c, hc, rfl⟩ hbc hr exact hs hb hc (ne_of_apply_ne _ hbc) (h hr)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image
null
preimage (hs : IsAntichain r s) {f : β → α} (hf : Injective f) (h : ∀ ⦃a b⦄, r' a b → r (f a) (f b)) : IsAntichain r' (f ⁻¹' s) := fun _ hb _ hc hbc hr => hs hb hc (hf.ne hbc) <| h hr
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage
null
_root_.isAntichain_insert : IsAntichain r (insert a s) ↔ IsAntichain r s ∧ ∀ ⦃b⦄, b ∈ s → a ≠ b → ¬r a b ∧ ¬r b a := Set.pairwise_insert
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
_root_.isAntichain_insert
null
protected insert (hs : IsAntichain r s) (hl : ∀ ⦃b⦄, b ∈ s → a ≠ b → ¬r b a) (hr : ∀ ⦃b⦄, b ∈ s → a ≠ b → ¬r a b) : IsAntichain r (insert a s) := isAntichain_insert.2 ⟨hs, fun _ hb hab => ⟨hr hb hab, hl hb hab⟩⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
insert
null
_root_.isAntichain_insert_of_symmetric (hr : Symmetric r) : IsAntichain r (insert a s) ↔ IsAntichain r s ∧ ∀ ⦃b⦄, b ∈ s → a ≠ b → ¬r a b := pairwise_insert_of_symmetric hr.compl
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
_root_.isAntichain_insert_of_symmetric
null
insert_of_symmetric (hs : IsAntichain r s) (hr : Symmetric r) (h : ∀ ⦃b⦄, b ∈ s → a ≠ b → ¬r a b) : IsAntichain r (insert a s) := (isAntichain_insert_of_symmetric hr).2 ⟨hs, h⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
insert_of_symmetric
null
image_relEmbedding (hs : IsAntichain r s) (φ : r ↪r r') : IsAntichain r' (φ '' s) := by intro b hb b' hb' h₁ h₂ rw [Set.mem_image] at hb hb' obtain ⟨⟨a, has, rfl⟩, ⟨a', has', rfl⟩⟩ := hb, hb' exact hs has has' (fun haa' => h₁ (by rw [haa'])) (φ.map_rel_iff.mp h₂)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_relEmbedding
null
preimage_relEmbedding {t : Set β} (ht : IsAntichain r' t) (φ : r ↪r r') : IsAntichain r (φ ⁻¹' t) := fun _ ha _s ha' hne hle => ht ha ha' (fun h => hne (φ.injective h)) (φ.map_rel_iff.mpr hle)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage_relEmbedding
null
image_relIso (hs : IsAntichain r s) (φ : r ≃r r') : IsAntichain r' (φ '' s) := hs.image_relEmbedding φ.toRelEmbedding
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_relIso
null
preimage_relIso {t : Set β} (hs : IsAntichain r' t) (φ : r ≃r r') : IsAntichain r (φ ⁻¹' t) := hs.preimage_relEmbedding φ.toRelEmbedding
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage_relIso
null
image_relEmbedding_iff {φ : r ↪r r'} : IsAntichain r' (φ '' s) ↔ IsAntichain r s := ⟨fun h => (φ.injective.preimage_image s).subst (h.preimage_relEmbedding φ), fun h => h.image_relEmbedding φ⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_relEmbedding_iff
null
image_relIso_iff {φ : r ≃r r'} : IsAntichain r' (φ '' s) ↔ IsAntichain r s := @image_relEmbedding_iff _ _ _ _ _ (φ : r ↪r r')
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_relIso_iff
null
image_embedding [LE α] [LE β] (hs : IsAntichain (· ≤ ·) s) (φ : α ↪o β) : IsAntichain (· ≤ ·) (φ '' s) := image_relEmbedding hs _
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_embedding
null
preimage_embedding [LE α] [LE β] {t : Set β} (ht : IsAntichain (· ≤ ·) t) (φ : α ↪o β) : IsAntichain (· ≤ ·) (φ ⁻¹' t) := preimage_relEmbedding ht _
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage_embedding
null
image_embedding_iff [LE α] [LE β] {φ : α ↪o β} : IsAntichain (· ≤ ·) (φ '' s) ↔ IsAntichain (· ≤ ·) s := image_relEmbedding_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_embedding_iff
null
image_iso [LE α] [LE β] (hs : IsAntichain (· ≤ ·) s) (φ : α ≃o β) : IsAntichain (· ≤ ·) (φ '' s) := image_relEmbedding hs _
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_iso
null
image_iso_iff [LE α] [LE β] {φ : α ≃o β} : IsAntichain (· ≤ ·) (φ '' s) ↔ IsAntichain (· ≤ ·) s := image_relEmbedding_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_iso_iff
null
preimage_iso [LE α] [LE β] {t : Set β} (ht : IsAntichain (· ≤ ·) t) (φ : α ≃o β) : IsAntichain (· ≤ ·) (φ ⁻¹' t) := preimage_relEmbedding ht _
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage_iso
null
preimage_iso_iff [LE α] [LE β] {t : Set β} {φ : α ≃o β} : IsAntichain (· ≤ ·) (φ ⁻¹' t) ↔ IsAntichain (· ≤ ·) t := ⟨fun h => (φ.image_preimage t).subst (h.image_iso φ), fun h => h.preimage_iso _⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage_iso_iff
null
to_dual [LE α] (hs : IsAntichain (· ≤ ·) s) : @IsAntichain αᵒᵈ (· ≤ ·) s := fun _ ha _ hb hab => hs hb ha hab.symm
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
to_dual
null
to_dual_iff [LE α] : IsAntichain (· ≤ ·) s ↔ @IsAntichain αᵒᵈ (· ≤ ·) s := ⟨to_dual, to_dual⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
to_dual_iff
null
image_compl [BooleanAlgebra α] (hs : IsAntichain (· ≤ ·) s) : IsAntichain (· ≤ ·) (compl '' s) := (hs.image_embedding (OrderIso.compl α).toOrderEmbedding).flip
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image_compl
null
preimage_compl [BooleanAlgebra α] (hs : IsAntichain (· ≤ ·) s) : IsAntichain (· ≤ ·) (compl ⁻¹' s) := fun _ ha _ ha' hne hle => hs ha' ha (fun h => hne (compl_inj_iff.mp h.symm)) (compl_le_compl hle)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
preimage_compl
null
isAntichain_union : IsAntichain r (s ∪ t) ↔ IsAntichain r s ∧ IsAntichain r t ∧ ∀ a ∈ s, ∀ b ∈ t, a ≠ b → rᶜ a b ∧ rᶜ b a := by rw [IsAntichain, IsAntichain, IsAntichain, pairwise_union] @[deprecated (since := "2025-09-20")] alias isAntichain_singleton := IsAntichain.singleton
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isAntichain_union
null
Set.Subsingleton.isAntichain (hs : s.Subsingleton) (r : α → α → Prop) : IsAntichain r s := hs.pairwise _
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
Set.Subsingleton.isAntichain
null
subsingleton_of_isChain_of_isAntichain (hs : IsChain r s) (ht : IsAntichain r s) : s.Subsingleton := by intro x hx y hy by_contra! hne cases hs hx hy hne with | inl h => exact ht hx hy hne h | inr h => exact ht hy hx hne.symm h
lemma
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
subsingleton_of_isChain_of_isAntichain
A set which is simultaneously a chain and antichain is subsingleton.
isChain_and_isAntichain_iff_subsingleton : IsChain r s ∧ IsAntichain r s ↔ s.Subsingleton := ⟨fun h ↦ subsingleton_of_isChain_of_isAntichain h.1 h.2, fun h ↦ ⟨h.isChain, h.isAntichain _⟩⟩
lemma
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isChain_and_isAntichain_iff_subsingleton
null
inter_subsingleton_of_isChain_of_isAntichain (hs : IsChain r s) (ht : IsAntichain r t) : (s ∩ t).Subsingleton := subsingleton_of_isChain_of_isAntichain (hs.mono (by simp)) (ht.subset (by simp))
lemma
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
inter_subsingleton_of_isChain_of_isAntichain
The intersection of a chain and an antichain is subsingleton.
inter_subsingleton_of_isAntichain_of_isChain (hs : IsAntichain r s) (ht : IsChain r t) : (s ∩ t).Subsingleton := inter_comm _ _ ▸ inter_subsingleton_of_isChain_of_isAntichain ht hs
lemma
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
inter_subsingleton_of_isAntichain_of_isChain
The intersection of an antichain and a chain is subsingleton.
IsAntichain.not_lt (hs : IsAntichain (· ≤ ·) s) (ha : a ∈ s) (hb : b ∈ s) : ¬a < b := fun h => hs ha hb h.ne h.le
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.not_lt
null
isAntichain_and_least_iff : IsAntichain (· ≤ ·) s ∧ IsLeast s a ↔ s = {a} := ⟨fun h => eq_singleton_iff_unique_mem.2 ⟨h.2.1, fun _ hb => h.1.eq' hb h.2.1 (h.2.2 hb)⟩, by rintro rfl exact ⟨IsAntichain.singleton, isLeast_singleton⟩⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isAntichain_and_least_iff
null
isAntichain_and_greatest_iff : IsAntichain (· ≤ ·) s ∧ IsGreatest s a ↔ s = {a} := ⟨fun h => eq_singleton_iff_unique_mem.2 ⟨h.2.1, fun _ hb => h.1.eq hb h.2.1 (h.2.2 hb)⟩, by rintro rfl exact ⟨IsAntichain.singleton, isGreatest_singleton⟩⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isAntichain_and_greatest_iff
null
IsAntichain.least_iff (hs : IsAntichain (· ≤ ·) s) : IsLeast s a ↔ s = {a} := (and_iff_right hs).symm.trans isAntichain_and_least_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.least_iff
null
IsAntichain.greatest_iff (hs : IsAntichain (· ≤ ·) s) : IsGreatest s a ↔ s = {a} := (and_iff_right hs).symm.trans isAntichain_and_greatest_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.greatest_iff
null
IsLeast.antichain_iff (hs : IsLeast s a) : IsAntichain (· ≤ ·) s ↔ s = {a} := (and_iff_left hs).symm.trans isAntichain_and_least_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsLeast.antichain_iff
null
IsGreatest.antichain_iff (hs : IsGreatest s a) : IsAntichain (· ≤ ·) s ↔ s = {a} := (and_iff_left hs).symm.trans isAntichain_and_greatest_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsGreatest.antichain_iff
null
IsAntichain.bot_mem_iff [OrderBot α] (hs : IsAntichain (· ≤ ·) s) : ⊥ ∈ s ↔ s = {⊥} := isLeast_bot_iff.symm.trans hs.least_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.bot_mem_iff
null
IsAntichain.top_mem_iff [OrderTop α] (hs : IsAntichain (· ≤ ·) s) : ⊤ ∈ s ↔ s = {⊤} := isGreatest_top_iff.symm.trans hs.greatest_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.top_mem_iff
null
IsAntichain.minimal_mem_iff (hs : IsAntichain (· ≤ ·) s) : Minimal (· ∈ s) a ↔ a ∈ s := ⟨fun h ↦ h.prop, fun h ↦ ⟨h, fun _ hys hyx ↦ (hs.eq hys h hyx).symm.le⟩⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.minimal_mem_iff
null
IsAntichain.maximal_mem_iff (hs : IsAntichain (· ≤ ·) s) : Maximal (· ∈ s) a ↔ a ∈ s := hs.to_dual.minimal_mem_iff
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.maximal_mem_iff
null
IsAntichain.eq_setOf_maximal (ht : IsAntichain (· ≤ ·) t) (h : ∀ x, Maximal (· ∈ s) x → x ∈ t) (hs : ∀ a ∈ t, ∃ b, b ≤ a ∧ Maximal (· ∈ s) b) : {x | Maximal (· ∈ s) x} = t := by refine Set.ext fun x ↦ ⟨h _, fun hx ↦ ?_⟩ obtain ⟨y, hyx, hy⟩ := hs x hx rwa [← ht.eq (h y hy) hx hyx]
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.eq_setOf_maximal
If `t` is an antichain shadowing and including the set of maximal elements of `s`, then `t` *is* the set of maximal elements of `s`.
IsAntichain.eq_setOf_minimal (ht : IsAntichain (· ≤ ·) t) (h : ∀ x, Minimal (· ∈ s) x → x ∈ t) (hs : ∀ a ∈ t, ∃ b, a ≤ b ∧ Minimal (· ∈ s) b) : {x | Minimal (· ∈ s) x} = t := ht.to_dual.eq_setOf_maximal h hs
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.eq_setOf_minimal
If `t` is an antichain shadowed by and including the set of minimal elements of `s`, then `t` *is* the set of minimal elements of `s`.
IsAntichain.of_strictMonoOn_antitoneOn (hf : StrictMonoOn f s) (hf' : AntitoneOn f s) : IsAntichain (· ≤ ·) s := fun _a ha _b hb hab' hab ↦ (hf ha hb <| hab.lt_of_ne hab').not_ge (hf' ha hb hab)
lemma
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.of_strictMonoOn_antitoneOn
null
IsAntichain.of_monotoneOn_strictAntiOn (hf : MonotoneOn f s) (hf' : StrictAntiOn f s) : IsAntichain (· ≤ ·) s := fun _a ha _b hb hab' hab ↦ (hf ha hb hab).not_gt (hf' ha hb <| hab.lt_of_ne hab')
lemma
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsAntichain.of_monotoneOn_strictAntiOn
null
isAntichain_iff_forall_not_lt : IsAntichain (· ≤ ·) s ↔ ∀ ⦃a⦄, a ∈ s → ∀ ⦃b⦄, b ∈ s → ¬a < b := ⟨fun hs _ ha _ => hs.not_lt ha, fun hs _ ha _ hb h h' => hs ha hb <| h'.lt_of_ne h⟩
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isAntichain_iff_forall_not_lt
null
setOf_maximal_antichain (P : α → Prop) : IsAntichain (· ≤ ·) {x | Maximal P x} := fun _ hx _ ⟨hy, _⟩ hne hle ↦ hne (hle.antisymm <| hx.2 hy hle)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
setOf_maximal_antichain
null
setOf_minimal_antichain (P : α → Prop) : IsAntichain (· ≤ ·) {x | Minimal P x} := (setOf_maximal_antichain (α := αᵒᵈ) P).swap
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
setOf_minimal_antichain
null
IsStrongAntichain (r : α → α → Prop) (s : Set α) : Prop := s.Pairwise fun a b => ∀ c, ¬r a c ∨ ¬r b c
def
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
IsStrongAntichain
A strong (upward) antichain is a set such that no two distinct elements are related to a common element.
protected subset (hs : IsStrongAntichain r s) (h : t ⊆ s) : IsStrongAntichain r t := hs.mono h
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
subset
null
mono (hs : IsStrongAntichain r₁ s) (h : r₂ ≤ r₁) : IsStrongAntichain r₂ s := hs.mono' fun _ _ hab c => (hab c).imp (compl_le_compl h _ _) (compl_le_compl h _ _)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
mono
null
eq (hs : IsStrongAntichain r s) {a b c : α} (ha : a ∈ s) (hb : b ∈ s) (hac : r a c) (hbc : r b c) : a = b := (Set.Pairwise.eq hs ha hb) fun h => False.elim <| (h c).elim (not_not_intro hac) (not_not_intro hbc)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
eq
null
protected isAntichain [IsRefl α r] (h : IsStrongAntichain r s) : IsAntichain r s := h.imp fun _ b hab => (hab b).resolve_right (not_not_intro <| refl _)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
isAntichain
null
protected subsingleton [IsDirected α r] (h : IsStrongAntichain r s) : s.Subsingleton := fun a ha b hb => let ⟨_, hac, hbc⟩ := directed_of r a b h.eq ha hb hac hbc
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
subsingleton
null
protected flip [IsSymm α r] (hs : IsStrongAntichain r s) : IsStrongAntichain (flip r) s := fun _ ha _ hb h c => (hs ha hb h c).imp (mt <| symm_of r) (mt <| symm_of r)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
flip
null
swap [IsSymm α r] (hs : IsStrongAntichain r s) : IsStrongAntichain (swap r) s := hs.flip
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
swap
null
image (hs : IsStrongAntichain r s) {f : α → β} (hf : Surjective f) (h : ∀ a b, r' (f a) (f b) → r a b) : IsStrongAntichain r' (f '' s) := by rintro _ ⟨a, ha, rfl⟩ _ ⟨b, hb, rfl⟩ hab c obtain ⟨c, rfl⟩ := hf c exact (hs ha hb (ne_of_apply_ne _ hab) _).imp (mt <| h _ _) (mt <| h _ _)
theorem
Order
[ "Mathlib.Order.Bounds.Basic", "Mathlib.Order.Preorder.Chain" ]
Mathlib/Order/Antichain.lean
image
null