mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Combinatorics.Additive.Corner.Roth

Goal state before:
pp: G : Type u_1
inst✝¹ : AddCommGroup G
inst✝ : Fintype G
ε : ℝ
hε : 0 < ε
hG : cornersTheoremBound ε ≤ Fintype.card G
A : Finset G
hAε : ε * ↑(Fintype.card G) ≤ ↑(#A)
hA : ThreeAPFree ↑A
⊢ False

Tactic:
let B : Finset (G × G) := univ.filter fun (x, y) ↦ y - x ∈ A
  have : ε * card G ^ 2 ≤ #B := by
    calc
      _ = card G * (ε * card G) := by ring
      _ ≤ card G * #A := by gcongr
      _ = #B := ?_
    norm_cast
    rw [← card_univ, ← card_product]
    exact card_equiv ((Equiv.refl _).prodShear fun a ↦ Equiv.addLeft a) (by simp [B])
  obtain ⟨x₁, y₁, x₂, y₂, hx₁y₁, hx₁y₂, hx₂y₁, hxy, hx₁x₂⟩ :
      ∃ x₁ y₁ x₂ y₂, y₁ - x₁ ∈ A ∧ y₂ - x₁ ∈ A ∧ y₁ - x₂ ∈ A ∧ x₁ + y₂ = x₂ + y₁ ∧ x₁ ≠ x₂ := by
    simpa [IsCornerFree, isCorner_iff, B, -exists_and_left, -exists_and_right]
      using corners_theorem ε hε hG B this
  have := hA hx₂y₁ hx₁y₁ hx₁y₂ <| by -- TODO: This really ought to just be `by linear_combination h`
    rw [sub_add_sub_comm, add_comm, add_sub_add_comm, add_right_cancel_iff,
      sub_eq_sub_iff_add_eq_add, add_comm, hxy, add_comm]
  exact hx₁x₂ <| by simpa using this.symm

Goal state after:
Module: Mathlib.FieldTheory.ChevalleyWarning

Goal state before:
pp: K : Type u_1
σ : Type u_2
ι : Type u_3
inst✝⁶ : Fintype K
inst✝⁵ : Field K
inst✝⁴ : Fintype σ
inst✝³ : DecidableEq σ
inst✝² : DecidableEq K
p : ℕ
inst✝¹ : CharP K p
inst✝ : Fintype ι
f : ι → MvPolynomial σ K
h : ∑ i, (f i).totalDegree < Fintype.card σ
⊢ p ∣ Fintype.card { x // ∀ (i : ι), (eval x) (f i) = 0 }

Tactic:
by
  simpa using char_dvd_card_solutions_of_sum_lt p h

Goal state after:
Module: Mathlib.Combinatorics.Additive.SubsetSum

Goal state before:
pp: M : Type u_1
inst✝³ : DecidableEq M
inst✝² : AddCommMonoid M
A : Finset M
a : M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedCancelAddMonoid M
hA : ∀ x ∈ A, 0 < x
hAa : ∀ x ∈ A, x < a
ha : 0 < a
disjoint : Disjoint (insert 0 A) (a +ᵥ A.subsetSum)
insert_subset : insert 0 A ⊆ (insert a A).subsetSum
vadd_subset : a +ᵥ A.subsetSum ⊆ (insert a A).subsetSum
⊢ #A + #A.subsetSum < #A + 1 + #A.subsetSum

Tactic:
by gcongr; exact Nat.lt_add_one _

Goal state after:
Module: Mathlib.Combinatorics.Additive.SubsetSum

Goal state before:
pp: case insert
M : Type u_1
inst✝³ : DecidableEq M
inst✝² : AddCommMonoid M
A✝ : Finset M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedCancelAddMonoid M
a : M
A : Finset M
A_lt_a : ∀ x ∈ A, x < a
ih : (∀ x ∈ A, 0 < x) → (#A + 1).choose 2 < #A.subsetSum
A_pos : ∀ x ∈ insert a A, 0 < x
A_pos' : ∀ x ∈ A, 0 < x
⊢ #A + (#A + 1).choose 2 + 1 < #(insert a A).subsetSum

Tactic:
add_assoc,

Goal state after:
case insert
M : Type u_1
inst✝³ : DecidableEq M
inst✝² : AddCommMonoid M
A✝ : Finset M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedCancelAddMonoid M
a : M
A : Finset M
A_lt_a : ∀ x ∈ A, x < a
ih : (∀ x ∈ A, 0 < x) → (#A + 1).choose 2 < #A.subsetSum
A_pos : ∀ x ∈ insert a A, 0 < x
A_pos' : ∀ x ∈ A, 0 < x
⊢ #A + ((#A + 1).choose 2 + 1) < #(insert a A).subsetSum
Module: Mathlib.Data.Nat.BitIndices

Goal state before:
pp: case succ
n k : ℕ
ih : (2 ^ k * n).bitIndices = map (fun x ↦ x + k) n.bitIndices
⊢ (2 * (2 ^ k * n)).bitIndices = map (fun x ↦ x + (1 + k)) n.bitIndices

Tactic:
bitIndices_two_mul,

Goal state after:
case succ
n k : ℕ
ih : (2 ^ k * n).bitIndices = map (fun x ↦ x + k) n.bitIndices
⊢ map (fun x ↦ x + 1) (2 ^ k * n).bitIndices = map (fun x ↦ x + (1 + k)) n.bitIndices
Module: Mathlib.Combinatorics.Colex

Goal state before:
pp: α : Type u_1
inst✝¹ : PartialOrder α
s : Finset α
a b : α
inst✝ : DecidableEq α
ha : a ∈ s
hb : b ∈ s
⊢ toColex (s.erase a) ≤ toColex (s.erase b) ↔ b ≤ a

Tactic:
by
  obtain rfl | hab := eq_or_ne a b
  · simp
  rw [← toColex_sdiff_le_toColex_sdiff', erase_sdiff_erase hab hb, erase_sdiff_erase hab.symm ha,
    singleton_le_singleton]

Goal state after:
Module: Mathlib.LinearAlgebra.Projectivization.Basic

Goal state before:
pp: case h.h
K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
u : V
hu : u ≠ 0
v : V
hv : v ≠ 0
h : K ∙ u = K ∙ v
⊢ mk K u hu = mk K v hv

Tactic:
Submodule.span_singleton_eq_span_singleton

Goal state after:
case h.h
K : Type u_1
V : Type u_2
inst✝² : DivisionRing K
inst✝¹ : AddCommGroup V
inst✝ : Module K V
u : V
hu : u ≠ 0
v : V
hv : v ≠ 0
h : ∃ z, z • u = v
⊢ mk K u hu = mk K v hv
Module: Mathlib.Combinatorics.Configuration

Goal state before:
pp: P : Type u_1
L : Type u_2
inst✝³ : Membership P L
inst✝² : Nondegenerate P L
inst✝¹ : Fintype P
inst✝ : Fintype L
h : Fintype.card L ≤ Fintype.card P
t : L → Finset P := fun l ↦ {p | p ∉ l}.toFinset
s : Finset L
hs₀ : ¬#s = 0
hs₁ : ¬#s = 1
p₁ p₂ : P
hp₁ : p₁ ∈ (s.biUnion fun l ↦ {p | p ∉ l}.toFinset)ᶜ
hp₂ : p₂ ∈ (s.biUnion fun l ↦ {p | p ∉ l}.toFinset)ᶜ
⊢ p₁ = p₂

Tactic:
Finset.mem_compl,

Goal state after:
P : Type u_1
L : Type u_2
inst✝³ : Membership P L
inst✝² : Nondegenerate P L
inst✝¹ : Fintype P
inst✝ : Fintype L
h : Fintype.card L ≤ Fintype.card P
t : L → Finset P := fun l ↦ {p | p ∉ l}.toFinset
s : Finset L
hs₀ : ¬#s = 0
hs₁ : ¬#s = 1
p₁ p₂ : P
hp₁ : p₁ ∉ s.biUnion fun l ↦ {p | p ∉ l}.toFinset
hp₂ : p₂ ∉ s.biUnion fun l ↦ {p | p ∉ l}.toFinset
⊢ p₁ = p₂
Module: Mathlib.LinearAlgebra.CrossProduct

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
u v w : Fin 3 → R
i : Fin (Nat.succ 0).succ.succ
⊢ ![u 1 * ![v 1 * w 2 - v 2 * w 1, v 2 * w 0 - v 0 * w 2, v 0 * w 1 - v 1 * w 0] 2 -
          u 2 * ![v 1 * w 2 - v 2 * w 1, v 2 * w 0 - v 0 * w 2, v 0 * w 1 - v 1 * w 0] 1,
        u 2 * ![v 1 * w 2 - v 2 * w 1, v 2 * w 0 - v 0 * w 2, v 0 * w 1 - v 1 * w 0] 0 -
          u 0 * ![v 1 * w 2 - v 2 * w 1, v 2 * w 0 - v 0 * w 2, v 0 * w 1 - v 1 * w 0] 2,
        u 0 * ![v 1 * w 2 - v 2 * w 1, v 2 * w 0 - v 0 * w 2, v 0 * w 1 - v 1 * w 0] 1 -
          u 1 * ![v 1 * w 2 - v 2 * w 1, v 2 * w 0 - v 0 * w 2, v 0 * w 1 - v 1 * w 0] 0]
      i =
    ((u 0 * w 0 + u 1 * w 1 + u 2 * w 2) • v - (v 0 * u 0 + v 1 * u 1 + v 2 * u 2) • w) i

Tactic:
fin_cases i <;>
  · simp only [Nat.succ_eq_add_one, Nat.reduceAdd, Fin.isValue, cons_val, cons_val_one,
      cons_val_zero, Fin.reduceFinMk, Pi.sub_apply, Pi.smul_apply, smul_eq_mul]
    ring

Goal state after:
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: case refine_1
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A : Finset G
a : G
hA : #(A * A) ≤ #A
ha : a ∈ A
smul_A : ∀ {a : G}, a ∈ A → a •> A = A * A
A_smul : ∀ {a : G}, a ∈ A → A <• a = A * A
smul_A_eq_A_smul : ∀ {a : G}, a ∈ A → a •> A = A <• a
mul_mem_A_comm : ∀ {x a : G}, a ∈ A → (x * a ∈ A ↔ a * x ∈ A)
H : Subgroup G := stabilizer G A
inv_smul_A : ∀ {a : G}, a ∈ A → a⁻¹ •> ↑A = ↑H
⊢ a •> ↑(stabilizer G A) = ↑A

Tactic:
← inv_smul_A ha,

Goal state after:
case refine_1
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A : Finset G
a : G
hA : #(A * A) ≤ #A
ha : a ∈ A
smul_A : ∀ {a : G}, a ∈ A → a •> A = A * A
A_smul : ∀ {a : G}, a ∈ A → A <• a = A * A
smul_A_eq_A_smul : ∀ {a : G}, a ∈ A → a •> A = A <• a
mul_mem_A_comm : ∀ {x a : G}, a ∈ A → (x * a ∈ A ↔ a * x ∈ A)
H : Subgroup G := stabilizer G A
inv_smul_A : ∀ {a : G}, a ∈ A → a⁻¹ •> ↑A = ↑H
⊢ a •> a⁻¹ •> ↑A = ↑A
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: case refine_2
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A : Finset G
a : G
hA : #(A * A) ≤ #A
ha : a ∈ A
smul_A : ∀ {a : G}, a ∈ A → a •> A = A * A
A_smul : ∀ {a : G}, a ∈ A → A <• a = A * A
smul_A_eq_A_smul : ∀ {a : G}, a ∈ A → a •> A = A <• a
mul_mem_A_comm : ∀ {x a : G}, a ∈ A → (x * a ∈ A ↔ a * x ∈ A)
H : Subgroup G := stabilizer G A
inv_smul_A : ∀ {a : G}, a ∈ A → a⁻¹ •> ↑A = ↑H
⊢ ↑(stabilizer G A) <• a = ↑A

Tactic:
← inv_smul_A ha,

Goal state after:
case refine_2
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A : Finset G
a : G
hA : #(A * A) ≤ #A
ha : a ∈ A
smul_A : ∀ {a : G}, a ∈ A → a •> A = A * A
A_smul : ∀ {a : G}, a ∈ A → A <• a = A * A
smul_A_eq_A_smul : ∀ {a : G}, a ∈ A → a •> A = A <• a
mul_mem_A_comm : ∀ {x a : G}, a ∈ A → (x * a ∈ A ↔ a * x ∈ A)
H : Subgroup G := stabilizer G A
inv_smul_A : ∀ {a : G}, a ∈ A → a⁻¹ •> ↑A = ↑H
⊢ a⁻¹ •> ↑A <• a = ↑A
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A B : Finset G
a b : G
ha : a ∈ B
hb : b ∈ B
this : #(a •> A ∪ b •> A) ≤ #(B * A)
⊢ 2 * #A ≤ #(a •> A ∩ b •> A) + #(B * A)

Tactic:
grw [← this, card_inter_add_card_union]

Goal state after:
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A B : Finset G
a b : G
ha : a ∈ B
hb : b ∈ B
this : #(a •> A ∪ b •> A) ≤ #(B * A)
⊢ 2 * #A ≤ #(a •> A) + #(b •> A)
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
K : ℝ
A B : Finset G
hA : ↑(#(B * A)) < K * ↑(#A)
a : G
ha : a ∈ B
b : G
hb : b ∈ B
⊢ (2 - K) * ↑(#A) < ↑(A.convolution A⁻¹ (a⁻¹ * b))

Tactic:
simpa [card_smul_inter_smul] using lt_card_smul_inter_smul hA ha hb

Goal state after:
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A : Finset G
h : ↑(#(A * A)) < 3 / 2 * ↑(#A)
a : G
ha : a ∈ A
z : G
hz : ∃ a_1, (∃ a ∈ A, ∃ z ∈ A, a⁻¹ * z = a_1) ∧ a * (a_1 * a) = z
⊢ z ∈ A * A

Tactic:
obtain ⟨d, ⟨b, hb, c, hc, rfl⟩, hz⟩ := hz

Goal state after:
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A : Finset G
h : ↑(#(A * A)) < 3 / 2 * ↑(#A)
a : G
ha : a ∈ A
z b : G
hb : b ∈ A
c : G
hc : c ∈ A
hz : a * (b⁻¹ * c * a) = z
⊢ z ∈ A * A
Module: Mathlib.Combinatorics.Enumerative.DyckWord

Goal state before:
pp: p : DyckWord
h : p ≠ 0
h' : ↑p ≠ []
this : take 1 (↑p).dropLast = [(↑p).head h']
⊢ U :: (↑p).dropLast.tail ++ [D] = (↑p).dropLast ++ [(↑p).getLast h']

Tactic:
← p.toList.dropLast.take_append_drop 1

Goal state after:
p : DyckWord
h : p ≠ 0
h' : ↑p ≠ []
this : take 1 (↑p).dropLast = [(↑p).head h']
⊢ U :: (↑p).dropLast.tail ++ [D] = take 1 (↑p).dropLast ++ drop 1 (↑p).dropLast ++ [(↑p).getLast h']
Module: Mathlib.Combinatorics.Enumerative.IncidenceAlgebra

Goal state before:
pp: F : Type u_1
𝕜 : Type u_2
𝕝 : Type u_3
𝕞 : Type u_4
α : Type u_5
β : Type u_6
inst✝⁵ : PartialOrder α
inst✝⁴ : LocallyFiniteOrder α
inst✝³ : DecidableEq α
inst✝² : CommSemiring 𝕜
inst✝¹ : CommSemiring 𝕝
inst✝ : Algebra 𝕜 𝕝
c : 𝕜
f : IncidenceAlgebra 𝕝 α
⊢ c • f = { toFun := fun c ↦ (algebraMap 𝕜 𝕝) c • 1, map_one' := ⋯, map_mul' := ⋯, map_zero' := ⋯, map_add' := ⋯ } c * f

Tactic:
classical ext a b hab; simp [if_pos hab, constSMul_apply, Algebra.smul_def]

Goal state after:
Module: Mathlib.Combinatorics.Enumerative.IncidenceAlgebra

Goal state before:
pp: 𝕜 : Type u_2
α : Type u_5
inst✝³ : Ring 𝕜
inst✝² : PartialOrder α
inst✝¹ : LocallyFiniteOrder α
inst✝ : DecidableEq α
a b : α
hab : a ≠ b
⊢ (mu 𝕜) a b = -∑ x ∈ Ioc a b, (mu 𝕜) x b

Tactic:
by
  rw [mu_eq_mu', mu'_eq_sum_Ioc_of_ne hab]

Goal state after:
Module: Mathlib.Combinatorics.Enumerative.DyckWord

Goal state before:
pp: case neg
p : DyckWord
h : ¬p = 0
⊢ ofTree p.toTree = p

Tactic:
· rw [toTree]
    simp_rw [h, ite_false, ofTree]
    rw [ofTree_toTree p.insidePart, ofTree_toTree p.outsidePart]
    exact nest_insidePart_add_outsidePart h

Goal state after:
Module: Mathlib.Combinatorics.Enumerative.Partition.Glaisher

Goal state before:
pp: R : Type u_1
inst✝¹ : CommRing R
inst✝ : NoZeroDivisors R
m : ℕ
hm : 0 < m
a✝ : Nontrivial R
x✝¹ : TopologicalSpace R := ⊥
x✝ : DiscreteTopology R
⊢ (PowerSeries.mk fun n ↦ ↑(#(restricted n fun x ↦ ¬m ∣ x))) = PowerSeries.mk fun n ↦ ↑(#(countRestricted n m))

Tactic:
powerSeriesMk_card_restricted_eq_tprod R (¬ m ∣ ·)

Goal state after:
R : Type u_1
inst✝¹ : CommRing R
inst✝ : NoZeroDivisors R
m : ℕ
hm : 0 < m
a✝ : Nontrivial R
x✝¹ : TopologicalSpace R := ⊥
x✝ : DiscreteTopology R
⊢ (∏' (i : ℕ), if ¬m ∣ i + 1 then ∑' (j : ℕ), X ^ ((i + 1) * j) else 1) =
    PowerSeries.mk fun n ↦ ↑(#(countRestricted n m))
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
K : ℝ
S : Finset G
hK : K < 1
hS : S.Nonempty
⊢ ∃ H x, IsAtom K S (↑H).toFinset

Tactic:
by
  -- We take any atom `N` of `G` with respect to `K` and `S`. Since left multiples of `N` (which
  -- are atoms as well) partition `G` by `IsAtom.eq_of_inter_nonempty`, we will deduce that a left
  -- multiple that contains `1` is a (finite) subgroup of `G`.
  obtain ⟨N, hN⟩ := exists_isAtom hK hS
  obtain ⟨n, hn⟩ := IsAtom.nonempty hK hS hN
  have one_mem_carrier : 1 ∈ n⁻¹ •> N := by simpa [mem_inv_smul_finset_iff]
  have self_mem_smul_carrier (x : G) : x ∈ x • n⁻¹ • N := by
    apply smul_mem_smul_finset (a := x) at one_mem_carrier
    simpa only [smul_eq_mul, mul_one] using! one_mem_carrier
  let H : Subgroup G := {
    carrier := n⁻¹ •> N
    one_mem' := mod_cast one_mem_carrier
    mul_mem' {a b} ha hb := by
      rw [← coe_smul_finset, mem_coe] at *
      apply smul_mem_smul_finset (a := a) at hb
      rw [smul_eq_mul] at hb
      have : (n⁻¹ •> N ∩ a •> n⁻¹ •> N).Nonempty := ⟨a, by
        simpa only [mem_inter] using! ⟨ha, self_mem_smul_carrier a⟩⟩
      simpa only [← (hN.smul_finset n⁻¹).eq_of_inter_nonempty hK.le hS
        ((hN.smul_finset n⁻¹).smul_finset a) this] using! hb
    inv_mem' {a} ha := by
      rw [← coe_smul_finset, mem_coe] at *
      apply smul_mem_smul_finset (a := a⁻¹) at ha
      rw [smul_eq_mul, inv_mul_cancel] at ha
      have : (n⁻¹ •> N ∩ a⁻¹ •> n⁻¹ •> N).Nonempty := ⟨1, by simpa using! ⟨one_mem_carrier, ha⟩⟩
      simpa only [← (hN.smul_finset n⁻¹).eq_of_inter_nonempty hK.le hS
        ((hN.smul_finset n⁻¹).smul_finset a⁻¹) this] using! self_mem_smul_carrier a⁻¹
  }
  refine ⟨H, Fintype.ofFinset (n⁻¹ •> N) fun a => ?_, ?_⟩
  · simpa only [← mem_coe, coe_smul_finset] using! H.mem_carrier
  · simpa [Set.toFinset_smul_set, toFinset_coe, H] using! IsAtom.smul_finset n⁻¹ hN

Goal state after:
Module: Mathlib.Combinatorics.Enumerative.Pentagonal.PowerSeries

Goal state before:
pp: case refine_1
R : Type u_1
inst✝³ : CommRing R
inst✝² : TopologicalSpace R
inst✝¹ : IsTopologicalRing R
inst✝ : T2Space R
a✝ : Nontrivial R
⊢ IsTopologicallyNilpotent X

Tactic:
IsTopologicallyNilpotent,

Goal state after:
case refine_1
R : Type u_1
inst✝³ : CommRing R
inst✝² : TopologicalSpace R
inst✝¹ : IsTopologicalRing R
inst✝ : T2Space R
a✝ : Nontrivial R
⊢ Tendsto (fun x ↦ X ^ x) atTop (𝓝 0)
Module: Mathlib.Combinatorics.Enumerative.Pentagonal.PowerSeries

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
n : ℕ
this✝ : TopologicalSpace R := ⊥
this : DiscreteTopology R
h :
  ∀ (d : ℕ),
    Tendsto (fun i ↦ (coeff d) (∏ b ∈ i, (1 - X ^ (b + 1)))) (SummationFilter.unconditional ℕ).filter
      (𝓝 ((coeff d) (pentagonalSeries R)))
⊢ ∀ᶠ (s : Finset ℕ) in atTop, (coeff n) (∏ n ∈ s, (1 - X ^ (n + 1))) = (coeff n) (pentagonalSeries R)

Tactic:
simpa using h n

Goal state after:
Module: Mathlib.Combinatorics.Extremal.RuzsaSzemeredi

Goal state before:
pp: case calc_1
n : ℕ
⊢ ↑n ≤ (2 * ↑(n / 6) + 1 + 2 - 1) * 3

Tactic:
add_assoc,

Goal state after:
case calc_1
n : ℕ
⊢ ↑n ≤ (2 * ↑(n / 6) + (1 + 2) - 1) * 3
Module: Mathlib.Combinatorics.Graph.Subgraph

Goal state before:
pp: case inr
α : Type u_1
β : Type u_2
e : β
G H : Graph α β
hHG : H ≤ G
he : e ∈ E(H)
u v : α
huv : H.IsLink e u v
h : G.IsLink e v u
⊢ H.IsLink e v u

Tactic:
exact huv.symm

Goal state after:
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: case hab
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
S : Finset G
ε : ℝ
hε₀ : 0 < ε
hε₁ : ε ≤ 1
hS : S.Nonempty
K : ℝ := 1 - ε / 2
hK : K < 1
ex : Finset G → ℝ := expansion K S
κ : ℝ := connectivity K S
H : Subgroup G
w✝ : Fintype ↥H
hH : IsAtom K S (↑H).toFinset
Z : Finset G
hZS : Z ⊆ S
hHZS : ↑H * ↑Z = ↑H * ↑S
hZinj : Set.InjOn (fun x ↦ ↑H <• x) ↑Z
A : Finset G
hA₁ : #S ≤ #A
hA₂ : ↑(#(A * S)) ≤ (2 - ε) * ↑(#S)
calc₁ : ex (↑H).toFinset ≤ (1 - ε / 2) * ↑(#S)
⊢ (1 - K) * ↑(#((↑H).toFinset * S)) ≤ (1 - ε / 2) * ↑(#(↑H).toFinset)

Tactic:
rw [sub_mul, one_mul, sub_le_iff_le_add]

Goal state after:
case hab
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
S : Finset G
ε : ℝ
hε₀ : 0 < ε
hε₁ : ε ≤ 1
hS : S.Nonempty
K : ℝ := 1 - ε / 2
hK : K < 1
ex : Finset G → ℝ := expansion K S
κ : ℝ := connectivity K S
H : Subgroup G
w✝ : Fintype ↥H
hH : IsAtom K S (↑H).toFinset
Z : Finset G
hZS : Z ⊆ S
hHZS : ↑H * ↑Z = ↑H * ↑S
hZinj : Set.InjOn (fun x ↦ ↑H <• x) ↑Z
A : Finset G
hA₁ : #S ≤ #A
hA₂ : ↑(#(A * S)) ≤ (2 - ε) * ↑(#S)
calc₁ : ex (↑H).toFinset ≤ (1 - ε / 2) * ↑(#S)
⊢ ↑(#((↑H).toFinset * S)) ≤ (1 - ε / 2) * ↑(#(↑H).toFinset) + K * ↑(#((↑H).toFinset * S))
Module: Mathlib.Combinatorics.Graph.Maps

Goal state before:
pp: α : Type u_1
α' : Type u_2
α'' : Type u_3
β : Type u_4
G✝ H : Graph α β
f✝ g : α → α'
u v : α
e✝ : β
x✝ y✝ : α'
f : α → α'
G : Graph α β
e : β
x y : α
hxy : G.IsLink e x y
z w : α
hzw : G.IsLink e z w
⊢ f x = f z ∨ f x = f w

Tactic:
obtain rfl | rfl := hxy.left_eq_or_eq hzw

Goal state after:
case inl
α : Type u_1
α' : Type u_2
α'' : Type u_3
β : Type u_4
G✝ H : Graph α β
f✝ g : α → α'
u v : α
e✝ : β
x✝ y✝ : α'
f : α → α'
G : Graph α β
e : β
x y : α
hxy : G.IsLink e x y
w : α
hzw : G.IsLink e x w
⊢ f x = f x ∨ f x = f w

case inr
α : Type u_1
α' : Type u_2
α'' : Type u_3
β : Type u_4
G✝ H : Graph α β
f✝ g : α → α'
u v : α
e✝ : β
x✝ y✝ : α'
f : α → α'
G : Graph α β
e : β
x y : α
hxy : G.IsLink e x y
z : α
hzw : G.IsLink e z x
⊢ f x = f z ∨ f x = f x
Module: Mathlib.Combinatorics.Hindman

Goal state before:
pp: M : Type u_1
inst✝ : CommMonoid M
a : Stream' M
s : Finset ℕ
hs : s.Nonempty
⊢ ∏ i ∈ s, a.get i ∈ FP (Stream'.drop (s.min' hs) a)

Tactic:
induction s using Finset.eraseInduction with

Goal state after:
case H
M : Type u_1
inst✝ : CommMonoid M
a : Stream' M
s : Finset ℕ
ih :
  ∀ s_1 ∈ s, ∀ (hs : (s.erase s_1).Nonempty), ∏ i ∈ s.erase s_1, a.get i ∈ FP (Stream'.drop ((s.erase s_1).min' hs) a)
hs : s.Nonempty
⊢ ∏ i ∈ s, a.get i ∈ FP (Stream'.drop (s.min' hs) a)
Module: Mathlib.Combinatorics.Hindman

Goal state before:
pp: M : Type u_1
inst✝ : CommMonoid M
a : Stream' M
s : Finset ℕ
hs : s.Nonempty
⊢ ∏ i ∈ s, a.get i ∈ FP a

Tactic:
refine FP_drop_subset_FP _ (s.min' hs) ?_
  induction s using Finset.eraseInduction with | H s ih => _
  rw [← Finset.mul_prod_erase _ _ (s.min'_mem hs), ← Stream'.head_drop]
  rcases (s.erase (s.min' hs)).eq_empty_or_nonempty with h | h
  · rw [h, Finset.prod_empty, mul_one]
    exact FP.head _
  · apply FP.cons
    rw [Stream'.tail_eq_drop, Stream'.drop_drop, add_comm]
    refine Set.mem_of_subset_of_mem ?_ (ih _ (s.min'_mem hs) h)
    have : s.min' hs + 1 ≤ (s.erase (s.min' hs)).min' h :=
      Nat.succ_le_of_lt (Finset.min'_lt_of_mem_erase_min' _ _ <| Finset.min'_mem _ _)
    obtain ⟨d, hd⟩ := Nat.exists_eq_add_of_le this
    rw [hd, ← Stream'.drop_drop, add_comm]
    apply FP_drop_subset_FP

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Minor.Contract

Goal state before:
pp: α : Type u_1
M : Matroid α
I X : Set α
hI : M.IsBasis I X
J : Set α
hJ : J ⊆ (M✶ ＼ I ＼ (X \ I)).E
e : α
he : e ∈ X \ I
⊢ e ∈ (M✶ ＼ I).coloops

Tactic:
by
    rw [← dual_contract, dual_coloops, ← IsLoop, ← singleton_dep, hI.indep.contract_dep_iff,
      singleton_union, and_iff_right (by simpa using he.2), hI.indep.insert_dep_iff,
      hI.closure_eq_closure]
    exact sdiff_subset_sdiff_left (M.subset_closure X) he

Goal state after:
Module: Mathlib.RingTheory.MvPolynomial.Groebner

Goal state before:
pp: case h.left
σ : Type u_1
m : MonomialOrder σ
R : Type u_2
inst✝ : CommRing R
ι : Type u_3
b : ι → MvPolynomial σ R
hb : ∀ (i : ι), IsUnit (m.leadingCoeff (b i))
f : MvPolynomial σ R
i : ι
hb0 : m.degree (b i) = 0
⊢ f = ⋯.unit⁻¹ • f * b i

Tactic:
simp only [smul_mul_assoc, ← smul_eq_iff_eq_inv_smul, Units.smul_isUnit]

Goal state after:
case h.left
σ : Type u_1
m : MonomialOrder σ
R : Type u_2
inst✝ : CommRing R
ι : Type u_3
b : ι → MvPolynomial σ R
hb : ∀ (i : ι), IsUnit (m.leadingCoeff (b i))
f : MvPolynomial σ R
i : ι
hb0 : m.degree (b i) = 0
⊢ m.leadingCoeff (b i) • f = f * b i
Module: Mathlib.RingTheory.MvPolynomial.Groebner

Goal state before:
pp: case h.left
σ : Type u_1
m : MonomialOrder σ
R : Type u_2
inst✝ : CommRing R
ι : Type u_3
b : ι → MvPolynomial σ R
hb : ∀ (i : ι), IsUnit (m.leadingCoeff (b i))
f : MvPolynomial σ R
hb' : ∀ (i : ι), m.degree (b i) ≠ 0
hf0 : ¬f = 0
i : ι
hf : m.degree (b i) ≤ m.degree f
deg_reduce : m.toSyn (m.degree (m.reduce ⋯ f)) < m.toSyn (m.degree f)
g' : ι →₀ MvPolynomial σ R
r' : MvPolynomial σ R
H' :
  m.reduce ⋯ f = (Finsupp.linearCombination (MvPolynomial σ R) b) g' + r' ∧
    (∀ (i_1 : ι), m.toSyn (m.degree (b i_1 * g' i_1)) ≤ m.toSyn (m.degree (m.reduce ⋯ f))) ∧
      ∀ c ∈ r'.support, ∀ (i : ι), ¬m.degree (b i) ≤ c
⊢ f =
    (Finsupp.linearCombination (MvPolynomial σ R) b) g' +
        (Finsupp.linearCombination (MvPolynomial σ R) b)
          (Finsupp.single i ((monomial (m.degree f - m.degree (b i))) (↑⋯.unit⁻¹ * m.leadingCoeff f))) +
      r'

Tactic:
add_assoc,

Goal state after:
case h.left
σ : Type u_1
m : MonomialOrder σ
R : Type u_2
inst✝ : CommRing R
ι : Type u_3
b : ι → MvPolynomial σ R
hb : ∀ (i : ι), IsUnit (m.leadingCoeff (b i))
f : MvPolynomial σ R
hb' : ∀ (i : ι), m.degree (b i) ≠ 0
hf0 : ¬f = 0
i : ι
hf : m.degree (b i) ≤ m.degree f
deg_reduce : m.toSyn (m.degree (m.reduce ⋯ f)) < m.toSyn (m.degree f)
g' : ι →₀ MvPolynomial σ R
r' : MvPolynomial σ R
H' :
  m.reduce ⋯ f = (Finsupp.linearCombination (MvPolynomial σ R) b) g' + r' ∧
    (∀ (i_1 : ι), m.toSyn (m.degree (b i_1 * g' i_1)) ≤ m.toSyn (m.degree (m.reduce ⋯ f))) ∧
      ∀ c ∈ r'.support, ∀ (i : ι), ¬m.degree (b i) ≤ c
⊢ f =
    (Finsupp.linearCombination (MvPolynomial σ R) b) g' +
      ((Finsupp.linearCombination (MvPolynomial σ R) b)
          (Finsupp.single i ((monomial (m.degree f - m.degree (b i))) (↑⋯.unit⁻¹ * m.leadingCoeff f))) +
        r')
Module: Mathlib.Combinatorics.Matroid.Minor.Contract

Goal state before:
pp: case inr
α : Type u_1
M : Matroid α
C : Set α
aux : ∀ {α : Type u_1} (M : Matroid α), ∀ C ⊆ M.E, M ／ M.closure C = M ／ C ＼ (M.closure C \ C)
hCE : ¬C ⊆ M.E
⊢ M ／ (C ∩ M.E) ＼ (M.closure (C ∩ M.E) \ (C ∩ M.E)) = M ／ (C ∩ M.E) ＼ (M.closure (C ∩ M.E) \ C)

Tactic:
sdiff_inter,

Goal state after:
case inr
α : Type u_1
M : Matroid α
C : Set α
aux : ∀ {α : Type u_1} (M : Matroid α), ∀ C ⊆ M.E, M ／ M.closure C = M ／ C ＼ (M.closure C \ C)
hCE : ¬C ⊆ M.E
⊢ M ／ (C ∩ M.E) ＼ (M.closure (C ∩ M.E) \ C ∪ M.closure (C ∩ M.E) \ M.E) = M ／ (C ∩ M.E) ＼ (M.closure (C ∩ M.E) \ C)
Module: Mathlib.Combinatorics.Optimization.ValuedCSP

Goal state before:
pp: D : Type u_1
C : Type u_3
inst✝² : AddCommMonoid C
inst✝¹ : PartialOrder C
inst✝ : IsOrderedCancelAddMonoid C
f : (Fin 2 → D) → C
ω : FractionalOperation D 2
valid : ω.IsValid
symmega : ω.IsSymmetric
a b : D
contr : 2 • (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum ≤ ω.size • 2 • f ![a, b]
hab : a ≠ b
mcfab : HasMaxCutPropertyAt f a b
half_sharp :
  (Multiset.map (fun x ↦ f ![a, b]) (ω.tt ![![a, b], ![b, a]])).sum < (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum
⊢ 2 • (Multiset.map (fun x ↦ f ![a, b]) (ω.tt ![![a, b], ![b, a]])).sum <
    2 • (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum

Tactic:
rw [two_nsmul, two_nsmul]

Goal state after:
D : Type u_1
C : Type u_3
inst✝² : AddCommMonoid C
inst✝¹ : PartialOrder C
inst✝ : IsOrderedCancelAddMonoid C
f : (Fin 2 → D) → C
ω : FractionalOperation D 2
valid : ω.IsValid
symmega : ω.IsSymmetric
a b : D
contr : 2 • (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum ≤ ω.size • 2 • f ![a, b]
hab : a ≠ b
mcfab : HasMaxCutPropertyAt f a b
half_sharp :
  (Multiset.map (fun x ↦ f ![a, b]) (ω.tt ![![a, b], ![b, a]])).sum < (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum
⊢ (Multiset.map (fun x ↦ f ![a, b]) (ω.tt ![![a, b], ![b, a]])).sum +
      (Multiset.map (fun x ↦ f ![a, b]) (ω.tt ![![a, b], ![b, a]])).sum <
    (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum + (Multiset.map f (ω.tt ![![a, b], ![b, a]])).sum