mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Combinatorics.SimpleGraph.Triangle.Counting

Goal state before:
pp: α : Type u_1
G : SimpleGraph α
inst✝ : DecidableRel G.Adj
ε : ℝ
s t u : Finset α
dst : 2 * ε ≤ ↑(G.edgeDensity s t)
hst : G.IsUniform ε s t
dsu : 2 * ε ≤ ↑(G.edgeDensity s u)
usu : G.IsUniform ε s u
dtu : 2 * ε ≤ ↑(G.edgeDensity t u)
utu : G.IsUniform ε t u
h₁ : ↑(#(G.badVertices ε s t)) ≤ ↑(#s) * ε
h₂ : ↑(#(G.badVertices ε s u)) ≤ ↑(#s) * ε
X' : Finset α := s \ (G.badVertices ε s t ∪ G.badVertices ε s u)
this✝ :
  (X'.biUnion fun x ↦ image (fun x_1 ↦ (x, x_1)) (G.interedges ({y ∈ t | G.Adj x y}) ({y ∈ u | G.Adj x y}))) ⊆
    {x ∈ s ×ˢ t ×ˢ u |
      match x with
      | (a, b, c) => G.Adj a b ∧ G.Adj a c ∧ G.Adj b c}
this : 0 ≤ ε
i : G.badVertices ε s t ∪ G.badVertices ε s u ⊆ s
⊢ ↑(#s) - 2 * ε * ↑(#s) ≤ ↑(#X')

Tactic:
card_sdiff_of_subset i,

Goal state after:
α : Type u_1
G : SimpleGraph α
inst✝ : DecidableRel G.Adj
ε : ℝ
s t u : Finset α
dst : 2 * ε ≤ ↑(G.edgeDensity s t)
hst : G.IsUniform ε s t
dsu : 2 * ε ≤ ↑(G.edgeDensity s u)
usu : G.IsUniform ε s u
dtu : 2 * ε ≤ ↑(G.edgeDensity t u)
utu : G.IsUniform ε t u
h₁ : ↑(#(G.badVertices ε s t)) ≤ ↑(#s) * ε
h₂ : ↑(#(G.badVertices ε s u)) ≤ ↑(#s) * ε
X' : Finset α := s \ (G.badVertices ε s t ∪ G.badVertices ε s u)
this✝ :
  (X'.biUnion fun x ↦ image (fun x_1 ↦ (x, x_1)) (G.interedges ({y ∈ t | G.Adj x y}) ({y ∈ u | G.Adj x y}))) ⊆
    {x ∈ s ×ˢ t ×ˢ u |
      match x with
      | (a, b, c) => G.Adj a b ∧ G.Adj a c ∧ G.Adj b c}
this : 0 ≤ ε
i : G.badVertices ε s t ∪ G.badVertices ε s u ⊆ s
⊢ ↑(#s) - 2 * ε * ↑(#s) ≤ ↑(#s - #(G.badVertices ε s t ∪ G.badVertices ε s u))
Module: Mathlib.Combinatorics.Additive.DoublingConst

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
A B : Finset G
hA : A.Nonempty
hB : B.Nonempty
⊢ 1 ≤ σₘ[A, B⁻¹]

Tactic:
apply one_le_mulConst hA (by simpa)

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

Goal state before:
pp: case neg
α : Type u_1
inst✝² : CommGroup α
inst✝¹ : DecidableEq α
inst✝ : Fintype α
s : Finset α
d : ℕ
hs : ∀ s' ⊆ s, MulDissociated ↑s' → #s' ≤ d
s' : Finset α
hs' : Maximal (fun x ↦ x ⊆ s ∧ MulDissociated ↑x) s'
a : α
ha : a ∈ s
ha' : a ∉ s'
t u : Finset α
ht : t ⊆ s'
hu : u ⊆ insert a s'
htu : Disjoint t u ∧ t ≠ u ∧ ∏ a ∈ t, a = ∏ a ∈ u, a
hat : a ∉ t
hau : a ∉ u
⊢ a ∈ s'.mulSpan

Tactic:
subset_insert_iff_of_notMem hau

Goal state after:
case neg
α : Type u_1
inst✝² : CommGroup α
inst✝¹ : DecidableEq α
inst✝ : Fintype α
s : Finset α
d : ℕ
hs : ∀ s' ⊆ s, MulDissociated ↑s' → #s' ≤ d
s' : Finset α
hs' : Maximal (fun x ↦ x ⊆ s ∧ MulDissociated ↑x) s'
a : α
ha : a ∈ s
ha' : a ∉ s'
t u : Finset α
ht : t ⊆ s'
hu : u ⊆ s'
htu : Disjoint t u ∧ t ≠ u ∧ ∏ a ∈ t, a = ∏ a ∈ u, a
hat : a ∉ t
hau : a ∉ u
⊢ a ∈ s'.mulSpan
Module: Mathlib.Combinatorics.Compactness

Goal state before:
pp: α : Type u_1
β : α → Type u_2
inst✝ : ∀ (a : α), Finite (β a)
g : (s : Set α) → s.Finite → (a : ↑s) → β ↑a
⊢ ∃ χ, ∀ (s : Set α), s.Finite → ∃ t, ∃ (ht : t.Finite) (hst : s ⊆ t), ∀ (x : ↑s), χ ↑x = g t ht (inclusion hst x)

Tactic:
by
  obtain ⟨χ, hχ⟩ := Finset.rado_selection_subtype (β := β) (fun s ↦ g s s.finite_toSet)
  refine ⟨χ, fun s hs ↦ ?_⟩
  obtain ⟨t, ht, hst⟩ := hχ hs.toFinset
  simp only [Set.Finite.toFinset_subset] at ht
  exact ⟨t, by simp_all⟩

Goal state after:
Module: Mathlib.LinearAlgebra.CrossProduct

Goal state before:
pp: R : Type u_1
inst✝ : CommRing R
u v w : Fin 3 → R
⊢ u ⬝ᵥ (crossProduct v) w = det ![u, v, w]

Tactic:
by
  rw [vec3_dotProduct, cross_apply, det_fin_three]
  dsimp only [Matrix.cons_val]
  ring

Goal state after:
Module: Mathlib.Combinatorics.Colex

Goal state before:
pp: case refine_2
α : Type u_1
inst✝ : LinearOrder α
s t : Finset α
w : α
hwt : w ∈ t
hws : w ∉ s
hw : ∀ ⦃a : α⦄, w < a → (a ∈ s ↔ a ∈ t)
a : α
has : a ∈ ofColex (toColex s)
hat : a ∉ ofColex (toColex t)
⊢ a < w

Tactic:
by_contra! hwa

Goal state after:
case refine_2
α : Type u_1
inst✝ : LinearOrder α
s t : Finset α
w : α
hwt : w ∈ t
hws : w ∉ s
hw : ∀ ⦃a : α⦄, w < a → (a ∈ s ↔ a ∈ t)
a : α
has : a ∈ ofColex (toColex s)
hat : a ∉ ofColex (toColex t)
hwa : w ≤ a
⊢ False
Module: Mathlib.Combinatorics.Colex

Goal state before:
pp: case inr.inl.inr
α : Type u_1
inst✝ : LinearOrder α
s t : Finset α
a : α
hcard : #s ≤ #t
ha : a ∈ s
ht : t.Nonempty
m : α := t.min' ht
h' : s ≠ t
w : α
hwt : w ∈ t
hws : w ∉ s
hw : ∀ ⦃a : α⦄, w < a → (a ∈ s ↔ a ∈ t)
hwa : w < a
hma : m < a
b : α
hbs : b ∈ ofColex { val := s.val.erase a, nodup := ⋯ }
hbt : b ∉ t
⊢ b < a

Tactic:
by_contra! hab
      exact hbt <| (hw <| hwa.trans_le hab).1 <| mem_of_mem_erase hbs

Goal state after:
Module: Mathlib.Combinatorics.Colex

Goal state before:
pp: α : Type u_1
inst✝ : LinearOrder α
s t : Finset α
a : α
hcard : #s ≤ #t
ha : a ∈ s
ht : t.Nonempty
m : α := t.min' ht
h' : s ≠ t
hwt : m ∈ t
hws : m ∉ s
hw : ∀ ⦃a : α⦄, m < a → (a ∈ s ↔ a ∈ t)
haw : a < m
b : α
hb : b ∈ t.erase m
⊢ b ∈ s.erase a

Tactic:
rw [mem_erase] at hb ⊢

Goal state after:
α : Type u_1
inst✝ : LinearOrder α
s t : Finset α
a : α
hcard : #s ≤ #t
ha : a ∈ s
ht : t.Nonempty
m : α := t.min' ht
h' : s ≠ t
hwt : m ∈ t
hws : m ∉ s
hw : ∀ ⦃a : α⦄, m < a → (a ∈ s ↔ a ∈ t)
haw : a < m
b : α
hb : b ≠ m ∧ b ∈ t
⊢ b ≠ a ∧ b ∈ s
Module: Mathlib.Combinatorics.Colex

Goal state before:
pp: n : ℕ
hn : 2 ≤ n
s t : Colex (Finset ℕ)
a : ℕ
hat : a ∈ ofColex t
has : a ∉ ofColex s
ha : ∀ b ∈ ofColex s, b ∉ ofColex t → b < a
⊢ ∑ i ∈ ofColex s \ ofColex t, n ^ i < ∑ i ∈ ofColex t \ ofColex s, n ^ i

Tactic:
exact (Nat.geomSum_lt hn <| by simpa).trans_le <| single_le_sum (fun _ _ ↦ by lia) <|
    mem_sdiff.2 ⟨hat, has⟩

Goal state after:
Module: Mathlib.Combinatorics.Derangements.Basic

Goal state before:
pp: case refine_1
α : Type u_1
β : Type u_2
p : α → Prop
inst✝ : DecidablePred p
f : Perm (Subtype p)
hf : f ∈ derangements (Subtype p)
a : α
ha : p a
hfa : ↑((Perm.subtypeEquivSubtypePerm p) f) a = a
⊢ ↑(f ⟨a, ha⟩) = ↑⟨a, ha⟩

Tactic:
Perm.subtypeEquivSubtypePerm,

Goal state after:
case refine_1
α : Type u_1
β : Type u_2
p : α → Prop
inst✝ : DecidablePred p
f : Perm (Subtype p)
hf : f ∈ derangements (Subtype p)
a : α
ha : p a
hfa :
  ↑({ toFun := fun f ↦ ⟨Perm.ofSubtype f, ⋯⟩, invFun := fun f ↦ (↑f).subtypePerm ⋯, left_inv := ⋯, right_inv := ⋯ } f)
      a =
    a
⊢ ↑(f ⟨a, ha⟩) = ↑⟨a, ha⟩
Module: Mathlib.Combinatorics.Enumerative.Catalan.Tree

Goal state before:
pp: case hi
n : ℕ
ih : ∀ m ≤ n, #(treesOfNumNodesEq m) = catalan m
⊢ (↑(antidiagonal n)).PairwiseDisjoint fun ij ↦ pairwiseNode (treesOfNumNodesEq ij.1) (treesOfNumNodesEq ij.2)

Tactic:
Set.PairwiseDisjoint,

Goal state after:
case hi
n : ℕ
ih : ∀ m ≤ n, #(treesOfNumNodesEq m) = catalan m
⊢ (↑(antidiagonal n)).Pairwise
    (Function.onFun Disjoint fun ij ↦ pairwiseNode (treesOfNumNodesEq ij.1) (treesOfNumNodesEq ij.2))
Module: Mathlib.Combinatorics.Enumerative.DyckWord

Goal state before:
pp: p q : DyckWord
h : p ≠ 0
⊢ List.drop (p.firstReturn + 1) ↑(p + q) =
    ↑({ toList := List.drop (p.firstReturn + 1) ↑p, count_U_eq_count_D := ⋯, count_D_le_count_U := ⋯ } + q)

Tactic:
exact drop_append_of_le_length (firstReturn_lt_length h)

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

Goal state before:
pp: case hg
R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : T2Space R
f : ℕ → ℕ → R
n : ℕ
p : n.Partition
s : Finset ℕ
hs : Icc 1 n ⊆ s
hs0 : 0 ∉ s
x : ℕ
hx : x ∈ s ∧ x ∉ p.parts.toFinset
⊢ (coeff (p.toFinsuppAntidiag x)) (1 + ∑' (j : ℕ), f x (j + 1) • X ^ (x * (j + 1))) = 1

Tactic:
Multiset.mem_toFinset

Goal state after:
case hg
R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : T2Space R
f : ℕ → ℕ → R
n : ℕ
p : n.Partition
s : Finset ℕ
hs : Icc 1 n ⊆ s
hs0 : 0 ∉ s
x : ℕ
hx : x ∈ s ∧ x ∉ p.parts
⊢ (coeff (p.toFinsuppAntidiag x)) (1 + ∑' (j : ℕ), f x (j + 1) • X ^ (x * (j + 1))) = 1
Module: Mathlib.Combinatorics.Additive.VerySmallDoubling

Goal state before:
pp: case a
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
K : ℝ
A : Finset G
hK₁ : 1 < K
hKφ : K < φ
hA₁ : ↑(#(A⁻¹ * A)) ≤ K * ↑(#A)
hA₂ : ↑(#(A * A⁻¹)) ≤ K * ↑(#A)
K_pos hK₀ : 0 < K
hKφ' : 0 < φ - K
hKψ' : 0 < K - ψ
hK₂' : 0 < 2 - K
const_pos : 0 < K * (2 - K) / ((φ - K) * (K - ψ))
A_nonempty : A.Nonempty
S : Finset G := ⋯
H : Subgroup G := ⋯
S_nonempty : S.Nonempty
this✝ : Finite ↥H
val✝ : Fintype ↥H
H_mul_S : ↑H * ↑S = ↑S
Z : Finset G
hZ : Z ⊆ S ∧ ↑H * ↑Z = ↑H * ↑S ∧ Set.InjOn (fun x ↦ ↑H <• x) ↑Z
H_mul_Z : ↑H * ↑Z = ↑S
H_toFinset_mul_Z : (↑H).toFinset * Z = S
card_H_mul_card_Z : Fintype.card ↥H * #Z = #S
r : G → ℕ := ⋯
r_inv : ∀ (z : G), r z⁻¹ = r z
z : G
hz : z ∈ S
w : G
hw : w ∈ S
hrz : (K - 1) * ↑(#A) < ↑(#(A ∩ z⁻¹ •> A))
hrw : (2 - K) * ↑(#A) ≤ ↑(#(A ∩ w •> A))
this : ↑(#(A ∩ z⁻¹ •> A ∩ (A ∩ w •> A))) ≤ ↑(#(z⁻¹ •> A ∩ w •> A))
⊢ A ∩ z⁻¹ •> A ∪ A ∩ w •> A ⊆ A

Tactic:
exact union_subset inter_subset_left inter_subset_left

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

Goal state before:
pp: case hfg
R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : T2Space R
f : ℕ → ℕ → R
n : ℕ
p : n.Partition
s : Finset ℕ
hs : Icc 1 n ⊆ s
hs0 : 0 ∉ s
i : ℕ
hi : i ∈ p.parts.toFinset
⊢ f i (Multiset.count i p.parts) = (coeff (p.toFinsuppAntidiag i)) (1 + ∑' (j : ℕ), f i (j + 1) • X ^ (i * (j + 1)))

Tactic:
Multiset.mem_toFinset

Goal state after:
case hfg
R : Type u_1
inst✝² : CommSemiring R
inst✝¹ : TopologicalSpace R
inst✝ : T2Space R
f : ℕ → ℕ → R
n : ℕ
p : n.Partition
s : Finset ℕ
hs : Icc 1 n ⊆ s
hs0 : 0 ∉ s
i : ℕ
hi : i ∈ p.parts
⊢ f i (Multiset.count i p.parts) = (coeff (p.toFinsuppAntidiag i)) (1 + ∑' (j : ℕ), f i (j + 1) • X ^ (i * (j + 1)))
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
N : Finset G
hN : IsAtom K S N
n : G
hn : n ∈ N
one_mem_carrier : 1 ∈ n⁻¹ •> N
self_mem_smul_carrier : ∀ (x : G), x ∈ x •> n⁻¹ •> N
a b : G
ha : a ∈ n⁻¹ •> ↑N
hb : b ∈ n⁻¹ •> ↑N
⊢ a * b ∈ n⁻¹ •> ↑N

Tactic:
← coe_smul_finset,

Goal state after:
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
K : ℝ
S : Finset G
hK : K < 1
hS : S.Nonempty
N : Finset G
hN : IsAtom K S N
n : G
hn : n ∈ N
one_mem_carrier : 1 ∈ n⁻¹ •> N
self_mem_smul_carrier : ∀ (x : G), x ∈ x •> n⁻¹ •> N
a b : G
ha : a ∈ ↑(n⁻¹ •> N)
hb : b ∈ ↑(n⁻¹ •> N)
⊢ a * b ∈ ↑(n⁻¹ •> N)
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
N : Finset G
hN : IsAtom K S N
n : G
hn : n ∈ N
one_mem_carrier : 1 ∈ n⁻¹ •> N
self_mem_smul_carrier : ∀ (x : G), x ∈ x •> n⁻¹ •> N
a : G
ha : a ∈ n⁻¹ •> ↑N
⊢ a⁻¹ ∈ n⁻¹ •> ↑N

Tactic:
← coe_smul_finset,

Goal state after:
G : Type u_1
inst✝¹ : Group G
inst✝ : DecidableEq G
K : ℝ
S : Finset G
hK : K < 1
hS : S.Nonempty
N : Finset G
hN : IsAtom K S N
n : G
hn : n ∈ N
one_mem_carrier : 1 ∈ n⁻¹ •> N
self_mem_smul_carrier : ∀ (x : G), x ∈ x •> n⁻¹ •> N
a : G
ha : a ∈ ↑(n⁻¹ •> N)
⊢ a⁻¹ ∈ ↑(n⁻¹ •> N)
Module: Mathlib.Combinatorics.HalesJewett

Goal state before:
pp: η : Type u_5
α : Type u_6
ι : Type u_7
κ : Type u_8
l : Subspace η α ι
η' : Type u_9
α' : Type u_10
ι' : Type u_11
eη : η ≃ η'
eα : α ≃ α'
eι : ι ≃ ι'
C : (ι → α) → κ
hl : IsMono C l
⊢ IsMono (fun x ↦ C (⇑eα.symm ∘ x ∘ ⇑eι)) (l.reindex eη eα eι)

Tactic:
simp [reindex_isMono, Function.comp_assoc]

Goal state after:
η : Type u_5
α : Type u_6
ι : Type u_7
κ : Type u_8
l : Subspace η α ι
η' : Type u_9
α' : Type u_10
ι' : Type u_11
eη : η ≃ η'
eα : α ≃ α'
eι : ι ≃ ι'
C : (ι → α) → κ
hl : IsMono C l
⊢ IsMono (fun x ↦ C (⇑eα.symm ∘ ⇑eα ∘ x)) l
Module: Mathlib.Combinatorics.Hypergraph.Basic

Goal state before:
pp: case inr
α : Type u_1
H : Hypergraph α
nonempty : V(H).Nonempty ∨ E(H).Nonempty
⊢ H.IsNonempty

Tactic:
grind [IsNonempty]

Goal state after:
Module: Mathlib.Combinatorics.KatonaCircle

Goal state before:
pp: X : Type u_1
inst✝¹ : Fintype X
f✝ : Numbering X
s✝ t : Finset X
inst✝ : DecidableEq X
s : Finset X
f : ↥(prefixed s)
x : X
hx✝ : x ∈ sᶜ
hx : x ∉ s
⊢ (fun n ↦ ⟨(Equiv.symm ↑f) ⟨↑n + #s, ⋯⟩, ⋯⟩) ((fun x ↦ ⟨↑(↑f ↑x) - #s, ⋯⟩) ⟨x, hx✝⟩) = ⟨x, hx✝⟩

Tactic:
mem_prefixed.1 f.2,

Goal state after:
X : Type u_1
inst✝¹ : Fintype X
f✝ : Numbering X
s✝ t : Finset X
inst✝ : DecidableEq X
s : Finset X
f : ↥(prefixed s)
x : X
hx✝ : x ∈ sᶜ
hx : ¬↑(↑f x) < #s
⊢ (fun n ↦ ⟨(Equiv.symm ↑f) ⟨↑n + #s, ⋯⟩, ⋯⟩) ((fun x ↦ ⟨↑(↑f ↑x) - #s, ⋯⟩) ⟨x, hx✝⟩) = ⟨x, hx✝⟩
Module: Mathlib.Combinatorics.KatonaCircle

Goal state before:
pp: case neg
X : Type u_1
inst✝¹ : Fintype X
f✝ : Numbering X
s✝ t : Finset X
inst✝ : DecidableEq X
s : Finset X
f : ↥(prefixed s)
x : X
hx : x ∉ s
⊢ ↑(↑((fun x ↦
              match x with
              | (g, g') =>
                ⟨{ toFun := fun x ↦ if hx : x ∈ s then Fin.castLE ⋯ (g ⟨x, hx⟩) else Fin.cast ⋯ ((g' ⟨x, ⋯⟩).addNat #s),
                    invFun := fun n ↦
                      if hn : ↑n < #s then ↑((Equiv.symm g) ⟨↑n, ⋯⟩) else ↑((Equiv.symm g') ⟨↑n - #s, ⋯⟩),
                    left_inv := ⋯, right_inv := ⋯ },
                  ⋯⟩)
            ((fun f ↦
                ({ toFun := fun x ↦ ⟨↑(↑f ↑x), ⋯⟩, invFun := fun n ↦ ⟨(Equiv.symm ↑f) ⟨↑n, ⋯⟩, ⋯⟩, left_inv := ⋯,
                    right_inv := ⋯ },
                  { toFun := fun x ↦ ⟨↑(↑f ↑x) - #s, ⋯⟩, invFun := fun n ↦ ⟨(Equiv.symm ↑f) ⟨↑n + #s, ⋯⟩, ⋯⟩,
                    left_inv := ⋯, right_inv := ⋯ }))
              f))
        x) =
    ↑(↑f x)

Tactic:
mem_prefixed.1 f.2,

Goal state after:
case neg
X : Type u_1
inst✝¹ : Fintype X
f✝ : Numbering X
s✝ t : Finset X
inst✝ : DecidableEq X
s : Finset X
f : ↥(prefixed s)
x : X
hx : ¬↑(↑f x) < #s
⊢ ↑(↑((fun x ↦
              match x with
              | (g, g') =>
                ⟨{ toFun := fun x ↦ if hx : x ∈ s then Fin.castLE ⋯ (g ⟨x, hx⟩) else Fin.cast ⋯ ((g' ⟨x, ⋯⟩).addNat #s),
                    invFun := fun n ↦
                      if hn : ↑n < #s then ↑((Equiv.symm g) ⟨↑n, ⋯⟩) else ↑((Equiv.symm g') ⟨↑n - #s, ⋯⟩),
                    left_inv := ⋯, right_inv := ⋯ },
                  ⋯⟩)
            ((fun f ↦
                ({ toFun := fun x ↦ ⟨↑(↑f ↑x), ⋯⟩, invFun := fun n ↦ ⟨(Equiv.symm ↑f) ⟨↑n, ⋯⟩, ⋯⟩, left_inv := ⋯,
                    right_inv := ⋯ },
                  { toFun := fun x ↦ ⟨↑(↑f ↑x) - #s, ⋯⟩, invFun := fun n ↦ ⟨(Equiv.symm ↑f) ⟨↑n + #s, ⋯⟩, ⋯⟩,
                    left_inv := ⋯, right_inv := ⋯ }))
              f))
        x) =
    ↑(↑f x)
Module: Mathlib.Combinatorics.Nullstellensatz

Goal state before:
pp: R : Type u_1
inst✝² : CommRing R
σ✝ : Type u_2
inst✝¹ : Finite σ✝
inst✝ : IsDomain R
σ τ : Type u_2
e : σ ≃ τ
h :
  ∀ (P : MvPolynomial σ R) (S : σ → Finset R),
    (∀ (i : σ), degreeOf i P < #(S i)) → (∀ (x : σ → R), (∀ (i : σ), x i ∈ S i) → (eval x) P = 0) → P = 0
P : MvPolynomial τ R
S : τ → Finset R
Hdeg : ∀ (i : τ), degreeOf i P < #(S i)
Heval : ∀ (x : τ → R), (∀ (i : τ), x i ∈ S i) → (eval x) P = 0
i : σ
| degreeOf i ((rename ⇑e.symm) P)

Tactic:
← e.symm_apply_apply i,

Goal state after:
R : Type u_1
inst✝² : CommRing R
σ✝ : Type u_2
inst✝¹ : Finite σ✝
inst✝ : IsDomain R
σ τ : Type u_2
e : σ ≃ τ
h :
  ∀ (P : MvPolynomial σ R) (S : σ → Finset R),
    (∀ (i : σ), degreeOf i P < #(S i)) → (∀ (x : σ → R), (∀ (i : σ), x i ∈ S i) → (eval x) P = 0) → P = 0
P : MvPolynomial τ R
S : τ → Finset R
Hdeg : ∀ (i : τ), degreeOf i P < #(S i)
Heval : ∀ (x : τ → R), (∀ (i : τ), x i ∈ S i) → (eval x) P = 0
i : σ
| degreeOf (e.symm (e i)) ((rename ⇑e.symm) P)
Module: Mathlib.Combinatorics.Matroid.Minor.Contract

Goal state before:
pp: α : Type u_1
M : Matroid α
K C : Set α
hK : M.IsCircuit K
hC : C ⊂ K
⊢ (M ／ C).IsCircuit (K \ C)

Tactic:
by
  suffices ∀ e ∈ K, e ∉ C → M.Indep (K \ {e} ∪ C) by
    simpa [isCircuit_iff_dep_forall_sdiff_singleton_indep, sdiff_sdiff_comm (s := K) (t := C),
    dep_iff, (hK.ssubset_indep hC).contract_indep_iff, sdiff_subset_sdiff_left hK.subset_ground,
    disjoint_sdiff_left, sdiff_union_of_subset hC.subset, hK.not_indep]
  exact fun e heK heC ↦ (hK.sdiff_singleton_indep heK).subset <| by
    simp [subset_sdiff_singleton hC.subset heC]

Goal state after:
Module: Mathlib.Combinatorics.Matroid.Sum

Goal state before:
pp: α : Type u_1
M N : Matroid α
h : Disjoint M.E N.E
B : Set α
hB : M.IsBase (B ∩ M.E) ∧ N.IsBase (B ∩ N.E) ∧ B ⊆ M.E ∪ N.E
⊢ ∃ BM BN, M.IsBase BM ∧ N.IsBase BN ∧ Disjoint BM BN ∧ B = BM ∪ BN

Tactic:
refine ⟨_, _, hB.1, hB.2.1, h.mono inter_subset_right inter_subset_right, ?_⟩

Goal state after:
α : Type u_1
M N : Matroid α
h : Disjoint M.E N.E
B : Set α
hB : M.IsBase (B ∩ M.E) ∧ N.IsBase (B ∩ N.E) ∧ B ⊆ M.E ∪ N.E
⊢ B = B ∩ M.E ∪ B ∩ N.E
Module: Mathlib.Combinatorics.Quiver.ConnectedComponent

Goal state before:
pp: V : Type u_2
inst✝ : Quiver V
h : IsStronglyConnected V
⊢ IsStronglyConnected (Symmetrify V)

Tactic:
intro a b
  obtain ⟨p⟩ := h a b
  induction p with
  | nil => exact ⟨Path.nil⟩
  | cons q e ih => exact ⟨ih.some.cons (Sum.inl e)⟩

Goal state after:
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
sharp :
  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
impos : 2 • (Multiset.map (fun x ↦ f ![a, b]) ω).sum < 2 • ω.size • f ![a, b]
rhs_swap : ω.size • 2 • f ![a, b] = 2 • ω.size • f ![a, b]
distrib : (Multiset.map (fun x ↦ f ![a, b]) ω).sum = ω.size • f ![a, b]
⊢ False

Tactic:
distrib

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
sharp :
  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
impos : 2 • ω.size • f ![a, b] < 2 • ω.size • f ![a, b]
rhs_swap : ω.size • 2 • f ![a, b] = 2 • ω.size • f ![a, b]
distrib : (Multiset.map (fun x ↦ f ![a, b]) ω).sum = ω.size • f ![a, b]
⊢ False
Module: Mathlib.Combinatorics.Nullstellensatz

Goal state before:
pp: case h.Heval
R : Type u_1
inst✝² : CommRing R
σ : Type u_2
inst✝¹ : Finite σ
inst✝ : IsDomain R
S : σ → Finset R
Sne : ∀ (i : σ), (S i).Nonempty
f : MvPolynomial σ R
Heval : ∀ (x : σ → R), (∀ (i : σ), x i ∈ S i) → (eval x) f = 0
this : LinearOrder σ := IsWellOrder.linearOrder WellOrderingRel
h : σ →₀ MvPolynomial σ R
r : MvPolynomial σ R
hf : f - (linearCombination (MvPolynomial σ R) fun i ↦ Alon.P (S i) i) h = r
hh : ∀ (i : σ), degLex.toSyn (degLex.degree (Alon.P (S i) i * h i)) ≤ degLex.toSyn (degLex.degree f)
hr : ∀ c ∈ r.support, ∀ (i : σ), ¬degLex.degree (Alon.P (S i) i) ≤ c
x : σ → R
hx : ∀ (i : σ), x i ∈ S i
⊢ ∑ a ∈ h.support, (eval x) (h a • Alon.P (S a) a) = 0

Tactic:
Finset.sum_eq_zero

Goal state after:
case h.Heval
R : Type u_1
inst✝² : CommRing R
σ : Type u_2
inst✝¹ : Finite σ
inst✝ : IsDomain R
S : σ → Finset R
Sne : ∀ (i : σ), (S i).Nonempty
f : MvPolynomial σ R
Heval : ∀ (x : σ → R), (∀ (i : σ), x i ∈ S i) → (eval x) f = 0
this : LinearOrder σ := IsWellOrder.linearOrder WellOrderingRel
h : σ →₀ MvPolynomial σ R
r : MvPolynomial σ R
hf : f - (linearCombination (MvPolynomial σ R) fun i ↦ Alon.P (S i) i) h = r
hh : ∀ (i : σ), degLex.toSyn (degLex.degree (Alon.P (S i) i * h i)) ≤ degLex.toSyn (degLex.degree f)
hr : ∀ c ∈ r.support, ∀ (i : σ), ¬degLex.degree (Alon.P (S i) i) ≤ c
x : σ → R
hx : ∀ (i : σ), x i ∈ S i
⊢ 0 = 0

case h.Heval
R : Type u_1
inst✝² : CommRing R
σ : Type u_2
inst✝¹ : Finite σ
inst✝ : IsDomain R
S : σ → Finset R
Sne : ∀ (i : σ), (S i).Nonempty
f : MvPolynomial σ R
Heval : ∀ (x : σ → R), (∀ (i : σ), x i ∈ S i) → (eval x) f = 0
this : LinearOrder σ := IsWellOrder.linearOrder WellOrderingRel
h : σ →₀ MvPolynomial σ R
r : MvPolynomial σ R
hf : f - (linearCombination (MvPolynomial σ R) fun i ↦ Alon.P (S i) i) h = r
hh : ∀ (i : σ), degLex.toSyn (degLex.degree (Alon.P (S i) i * h i)) ≤ degLex.toSyn (degLex.degree f)
hr : ∀ c ∈ r.support, ∀ (i : σ), ¬degLex.degree (Alon.P (S i) i) ≤ c
x : σ → R
hx : ∀ (i : σ), x i ∈ S i
⊢ ∀ x_1 ∈ h.support, (eval x) (h x_1 • Alon.P (S x_1) x_1) = 0
Module: Mathlib.Combinatorics.Nullstellensatz

Goal state before:
pp: case neg
R : Type u_1
inst✝² : CommRing R
σ : Type u_2
inst✝¹ : Finite σ
inst✝ : IsDomain R
f : MvPolynomial σ R
t : σ →₀ ℕ
ht : coeff t f ≠ 0
ht' : f.totalDegree = Finsupp.degree t
S : σ → Finset R
htS : ∀ (i : σ), t i < #(S i)
x✝ : LinearOrder σ := IsWellOrder.linearOrder WellOrderingRel
Heval : ∀ (s : σ → R), (∀ (i : σ), s i ∈ S i) → (eval s) f = 0
h : σ →₀ MvPolynomial σ R
hh : ∀ (i : σ), ((∏ s ∈ S i, (X i - C s)) * h i).totalDegree ≤ f.totalDegree
hf : f = (linearCombination (MvPolynomial σ R) fun i ↦ ∏ r ∈ S i, (X i - C r)) h
i : σ
a✝ : i ∈ h.support
g : MvPolynomial σ R := h i * Alon.P (S i) i
hg : g = h i * Alon.P (S i) i
hi : ¬h i = 0
this : (h i).totalDegree + #(S i) ≤ Finsupp.degree t
⊢ ∑ x ∈ Finset.antidiagonal t, coeff x.1 (h i) * coeff x.2 (∏ r ∈ S i, (X i - C r)) = 0

Tactic:
Finset.sum_eq_zero

Goal state after:
case neg
R : Type u_1
inst✝² : CommRing R
σ : Type u_2
inst✝¹ : Finite σ
inst✝ : IsDomain R
f : MvPolynomial σ R
t : σ →₀ ℕ
ht : coeff t f ≠ 0
ht' : f.totalDegree = Finsupp.degree t
S : σ → Finset R
htS : ∀ (i : σ), t i < #(S i)
x✝ : LinearOrder σ := IsWellOrder.linearOrder WellOrderingRel
Heval : ∀ (s : σ → R), (∀ (i : σ), s i ∈ S i) → (eval s) f = 0
h : σ →₀ MvPolynomial σ R
hh : ∀ (i : σ), ((∏ s ∈ S i, (X i - C s)) * h i).totalDegree ≤ f.totalDegree
hf : f = (linearCombination (MvPolynomial σ R) fun i ↦ ∏ r ∈ S i, (X i - C r)) h
i : σ
a✝ : i ∈ h.support
g : MvPolynomial σ R := h i * Alon.P (S i) i
hg : g = h i * Alon.P (S i) i
hi : ¬h i = 0
this : (h i).totalDegree + #(S i) ≤ Finsupp.degree t
⊢ 0 = 0

case neg
R : Type u_1
inst✝² : CommRing R
σ : Type u_2
inst✝¹ : Finite σ
inst✝ : IsDomain R
f : MvPolynomial σ R
t : σ →₀ ℕ
ht : coeff t f ≠ 0
ht' : f.totalDegree = Finsupp.degree t
S : σ → Finset R
htS : ∀ (i : σ), t i < #(S i)
x✝ : LinearOrder σ := IsWellOrder.linearOrder WellOrderingRel
Heval : ∀ (s : σ → R), (∀ (i : σ), s i ∈ S i) → (eval s) f = 0
h : σ →₀ MvPolynomial σ R
hh : ∀ (i : σ), ((∏ s ∈ S i, (X i - C s)) * h i).totalDegree ≤ f.totalDegree
hf : f = (linearCombination (MvPolynomial σ R) fun i ↦ ∏ r ∈ S i, (X i - C r)) h
i : σ
a✝ : i ∈ h.support
g : MvPolynomial σ R := h i * Alon.P (S i) i
hg : g = h i * Alon.P (S i) i
hi : ¬h i = 0
this : (h i).totalDegree + #(S i) ≤ Finsupp.degree t
⊢ ∀ x ∈ Finset.antidiagonal t, coeff x.1 (h i) * coeff x.2 (∏ r ∈ S i, (X i - C r)) = 0
Module: Mathlib.Data.Set.Sups

Goal state before:
pp: α : Type u_2
inst✝ : SemilatticeSup α
s t : Set α
⊢ upperClosure (s ⊻ t) = upperClosure s ⊔ upperClosure t

Tactic:
by
  ext a
  simp only [SetLike.mem_coe, mem_upperClosure, Set.mem_sups,
    UpperSet.coe_sup, Set.mem_inter_iff]
  constructor
  · rintro ⟨_, ⟨b, hb, c, hc, rfl⟩, ha⟩
    exact ⟨⟨b, hb, le_sup_left.trans ha⟩, c, hc, le_sup_right.trans ha⟩
  · rintro ⟨⟨b, hb, hab⟩, c, hc, hac⟩
    exact ⟨_, ⟨b, hb, c, hc, rfl⟩, sup_le hab hac⟩

Goal state after:
Module: Mathlib.Combinatorics.SetFamily.Compression.Down

Goal state before:
pp: α : Type u_1
inst✝ : DecidableEq α
a : α
𝒜 : Finset (Finset α)
⊢ #(image (fun s ↦ s.erase a) ({s ∈ 𝒜 | a ∈ s})) + #(nonMemberSubfamily a 𝒜) = #𝒜

Tactic:
nonMemberSubfamily,

Goal state after:
α : Type u_1
inst✝ : DecidableEq α
a : α
𝒜 : Finset (Finset α)
⊢ #(image (fun s ↦ s.erase a) ({s ∈ 𝒜 | a ∈ s})) + #({s ∈ 𝒜 | a ∉ s}) = #𝒜