mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Combinatorics.Matroid.IndepAxioms

Goal state before:
pp: α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
⊢ ∃ x ∈ B \ I, Indep (insert x I)

Tactic:
by_cases heB : e ∈ B

Goal state after:
case pos
α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∈ B
⊢ ∃ x ∈ B \ I, Indep (insert x I)

case neg
α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∉ B
⊢ ∃ x ∈ B \ I, Indep (insert x I)
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
A : Type u_4
inst✝⁶ : CommSemiring R
inst✝⁵ : AddCommMonoid M
inst✝⁴ : Module R M
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
⊢ Function.Injective ⇑(toAlgebra e)

Tactic:
by

Goal state after:
Module: Mathlib.FieldTheory.PrimitiveElement

Goal state before:
pp: F : Type u_3
E : Type u_4
inst✝⁶ : Field F
inst✝⁵ : Field E
inst✝⁴ : Algebra F E
inst✝³ : FiniteDimensional F E
inst✝² : Algebra.IsSeparable F E
A : Type u_5
inst✝¹ : Field A
inst✝ : Algebra F A
hA : ∀ (x : E), (Polynomial.map (algebraMap F A) (minpoly F x)).Splits
α : E
⊢ F⟮α⟯ = ⊤ ↔ Function.Injective fun φ ↦ φ α

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X Y : Set α
hI : M.IsBasis I X
hIY : I ⊆ Y
hYX : Y ⊆ X
⊢ M.IsBasis I Y

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I : Set α
⊢ M.IsBasis I I ↔ M.Indep I

Tactic:
by

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

Goal state before:
pp: α : Type u_1
I : Set α
M : Matroid α
h : I = ∅
⊢ M.IsBasis I ∅

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
N : Type u_1
P : Type u_2
Q : Type u_3
A : Type u_4
inst✝¹² : CommSemiring R
inst✝¹¹ : AddCommMonoid M
inst✝¹⁰ : AddCommMonoid N
inst✝⁹ : AddCommMonoid P
inst✝⁸ : AddCommMonoid Q
inst✝⁷ : Module R M
inst✝⁶ : Module R N
inst✝⁵ : Module R P
inst✝⁴ : Module R Q
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
x : A ⊗[R] ↥(submoduleAlgebra e)
⊢ (LinearMap.mul'' R A ∘ₗ (AlgebraTensorModule.lTensor A A) (submoduleAlgebra e).subtype) 0 =
    (AlgebraTensorModule.congr (LinearEquiv.refl A A) (submoduleAlgebraEquiv e) ≪≫ₗ e) 0

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X Y : Set α
hI : M.IsBasis I X
hIY : I ⊂ Y
hYX : Y ⊆ X
⊢ M.Dep Y

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X : Set α
hI : M.Indep I
hIX : I ⊆ X
hX : X ⊆ M.E
⊢ ∃ J, M.IsBasis J X ∧ I ⊆ J

Tactic:
by

Goal state after:
Module: Mathlib.FieldTheory.PrimitiveElement

Goal state before:
pp: F : Type u_3
E : Type u_4
inst✝⁶ : Field F
inst✝⁵ : Field E
inst✝⁴ : Algebra F E
inst✝³ : FiniteDimensional F E
inst✝² : Algebra.IsSeparable F E
A : Type u_5
inst✝¹ : Field A
inst✝ : Algebra F A
hA : ∀ (x : E), (Polynomial.map (algebraMap F A) (minpoly F x)).Splits
α : E
φ : E →ₐ[F] A
⊢ F⟮α⟯ = ⊤ ↔ ∀ (ψ : E →ₐ[F] A), φ α = ψ α → φ = ψ

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X : Set α
hI : M.Indep I
hIX : I ⊆ X
⊢ ∃ J, M.IsBasis' J X ∧ I ⊆ J

Tactic:
by

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

Goal state before:
pp: α : Type u_1
X Y : Set α
M : Matroid α
hXY : X ⊆ Y
hY : Y ⊆ M.E
⊢ ∃ I J, M.IsBasis I X ∧ M.IsBasis J Y ∧ I ⊆ J

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
N : Type u_1
P : Type u_2
Q : Type u_3
A : Type u_4
inst✝¹² : CommSemiring R
inst✝¹¹ : AddCommMonoid M
inst✝¹⁰ : AddCommMonoid N
inst✝⁹ : AddCommMonoid P
inst✝⁸ : AddCommMonoid Q
inst✝⁷ : Module R M
inst✝⁶ : Module R N
inst✝⁵ : Module R P
inst✝⁴ : Module R Q
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
x : A ⊗[R] ↥(submoduleAlgebra e)
⊢ ∀ (x y : A ⊗[R] ↥(submoduleAlgebra e)),
    (LinearMap.mul'' R A ∘ₗ (AlgebraTensorModule.lTensor A A) (submoduleAlgebra e).subtype) x =
        (AlgebraTensorModule.congr (LinearEquiv.refl A A) (submoduleAlgebraEquiv e) ≪≫ₗ e) x →
      (LinearMap.mul'' R A ∘ₗ (AlgebraTensorModule.lTensor A A) (submoduleAlgebra e).subtype) y =
          (AlgebraTensorModule.congr (LinearEquiv.refl A A) (submoduleAlgebraEquiv e) ≪≫ₗ e) y →
        (LinearMap.mul'' R A ∘ₗ (AlgebraTensorModule.lTensor A A) (submoduleAlgebra e).subtype) (x + y) =
          (AlgebraTensorModule.congr (LinearEquiv.refl A A) (submoduleAlgebraEquiv e) ≪≫ₗ e) (x + y)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X Y : Set α
hI : M.IsBasis I X
hXY : X ⊆ Y
hY : Y ⊆ M.E
⊢ ∃ J, M.IsBasis J Y ∧ J ∩ X = I

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
X Y : Set α
hX : X ⊆ M.E
hY : Y ⊆ M.E
J : Set α
hJ : M.IsBasis J Y
I : Set α
hI : M.IsBasis I (X ∪ Y) ∧ I ∩ Y = J
⊢ M.IsBasis (I ∩ Y) Y

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M✝ : Matroid α
I B X : Set α
M : Matroid α
⊢ ∀ ⦃I J : Set α⦄, (J ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint J B) → I ⊆ J → I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X : Set α
hI : M.IsBasis I X
B : Set α
hB : M.IsBase B
hIB : I ⊆ B
⊢ B ∩ X ⊆ I

Tactic:
by

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

Goal state before:
pp: α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∉ B
hcon : ∀ x ∈ B \ I, ¬Indep (insert x I)
heBdep : ¬Indep (insert e B)
B₀ : Set α
hB₀B : B₀ ⊆ B
hB₀fin : B₀.Finite
hB₀e : ¬Indep (insert e B₀)
hB₀ : Indep B₀
⊢ ∀ (b : ↑(B₀ \ I)), ∃ Ib ⊆ I, Ib.Finite ∧ ¬Indep (insert (↑b) Ib)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
B : Set α
⊢ M.IsBasis B M.E ↔ M.IsBase B

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
N : Type u_1
P : Type u_2
Q : Type u_3
A : Type u_4
inst✝¹² : CommSemiring R
inst✝¹¹ : AddCommMonoid M
inst✝¹⁰ : AddCommMonoid N
inst✝⁹ : AddCommMonoid P
inst✝⁸ : AddCommMonoid Q
inst✝⁷ : Module R M
inst✝⁶ : Module R N
inst✝⁵ : Module R P
inst✝⁴ : Module R Q
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
x : A ⊗[R] ↥(submoduleAlgebra e)
a : A
m : M
this : a * (toAlgebra e) m = e (a ⊗ₜ[R] m)
⊢ (LinearMap.mul'' R A ∘ₗ (AlgebraTensorModule.lTensor A A) (submoduleAlgebra e).subtype)
      (a ⊗ₜ[R] (submoduleAlgebraEquiv e).symm m) =
    (AlgebraTensorModule.congr (LinearEquiv.refl A A) (submoduleAlgebraEquiv e) ≪≫ₗ e)
      (a ⊗ₜ[R] (submoduleAlgebraEquiv e).symm m)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X : Set α
hI : M.Indep I
hIX : I ⊆ X
⊢ M.IsBasis I X ↔ ∀ e ∈ X \ I, M.Dep (insert e I)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I : Set α
e : α
hI : M.Indep I
⊢ M.IsBasis I (insert e I) ↔ M.Dep (insert e I) ∨ e ∈ I

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
ι : Type u_2
X I : ι → Set α
hI : ∀ (i : ι), M.IsBasis (I i) (X i)
h_ind : M.Indep (⋃ i, I i)
⊢ M.IsBasis (⋃ i, I i) (⋃ i, X i)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I : Set α
ι : Type u_2
inst✝ : Nonempty ι
X : ι → Set α
hI : ∀ (i : ι), M.IsBasis I (X i)
⊢ M.IsBasis I (⋃ i, X i)

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
N : Type u_1
P : Type u_2
Q : Type u_3
A : Type u_4
inst✝¹² : CommSemiring R
inst✝¹¹ : AddCommMonoid M
inst✝¹⁰ : AddCommMonoid N
inst✝⁹ : AddCommMonoid P
inst✝⁸ : AddCommMonoid Q
inst✝⁷ : Module R M
inst✝⁶ : Module R N
inst✝⁵ : Module R P
inst✝⁴ : Module R Q
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
⊢ Function.Bijective ⇑(LinearMap.mul'' R A ∘ₗ (AlgebraTensorModule.lTensor A A) (submoduleAlgebra e).subtype)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I : Set α
Xs : Set (Set α)
hne : Xs.Nonempty
h : ∀ X ∈ Xs, M.IsBasis I X
⊢ M.IsBasis I (⋃₀ Xs)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I : Set α
hI : M.Indep I
⊢ M.IsBasis I {x | M.IsBasis I (insert x I)}

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
A : Type u_4
inst✝⁶ : CommSemiring R
inst✝⁵ : AddCommMonoid M
inst✝⁴ : Module R M
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
⊢ ⊤ * submoduleAlgebra e = ⊤

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M✝ : Matroid α
I✝ B✝ X✝ : Set α
M : Matroid α
I X : Set α
hIE : I ⊆ M.E
B : Set α
hB : M.IsBase B
hIB : Disjoint I B
hI_not_max : ¬Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) I
hX_max : Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) X
hXE : X ⊆ M.E
B' : Set α := M.E \ X
hB' : M.IsBase B'
hX : B' = M.E \ X
hI : ¬M.IsBase (M.E \ I)
B'' : Set α
hB'' : M.IsBase B''
hB''₁ : B' \ I ⊆ B''
hB''₂ : B'' ⊆ B' ∪ B ∧ I ⊆ B''ᶜ
⊢ I ≠ B''ᶜ ∩ M.E

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
M : Type v
N : Type u_1
P : Type u_2
Q : Type u_3
A : Type u_4
inst✝¹² : CommSemiring R
inst✝¹¹ : AddCommMonoid M
inst✝¹⁰ : AddCommMonoid N
inst✝⁹ : AddCommMonoid P
inst✝⁸ : AddCommMonoid Q
inst✝⁷ : Module R M
inst✝⁶ : Module R N
inst✝⁵ : Module R P
inst✝⁴ : Module R Q
inst✝³ : Semiring A
inst✝² : Algebra R A
e : A ⊗[R] M ≃ₗ[A] A
inst✝¹ : Flat R M
inst✝ : FaithfulSMul R A
I : Submodule R A
⊢ ↥I ⊗[R] ↥(submoduleAlgebra e) ≃ₗ[R] ↥(I * submoduleAlgebra e)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I J X Y : Set α
hIX : M.IsBasis I X
hJY : M.IsBasis J Y
h : M.Indep (I ∪ J)
⊢ M.IsBasis (I ∪ J) (X ∪ Y)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∉ B
hcon : ∀ x ∈ B \ I, ¬Indep (insert x I)
heBdep : ¬Indep (insert e B)
B₀ : Set α
hB₀B : B₀ ⊆ B
hB₀fin : B₀.Finite
hB₀e : ¬Indep (insert e B₀)
hB₀ : Indep B₀
⊢ ∃ I₀ ⊆ I, I₀.Finite ∧ ∀ x ∈ B₀ \ I₀, ¬Indep (insert x I₀)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X Y : Set α
hIX : M.IsBasis I X
hIY : M.IsBasis I Y
⊢ M.IsBasis I (X ∪ Y)

Tactic:
by

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

Goal state before:
pp: case neg
α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∉ B
hcon : ∀ x ∈ B \ I, ¬Indep (insert x I)
heBdep : ¬Indep (insert e B)
B₀ : Set α
hB₀B : B₀ ⊆ B
hB₀fin : B₀.Finite
hB₀e : ¬Indep (insert e B₀)
hB₀ : Indep B₀
⊢ False

Tactic:
have hexI₀ : ∃ I₀, I₀ ⊆ I ∧ I₀.Finite ∧ ∀ x, x ∈ B₀ \ I₀ → ¬Indep (insert x I₀) := by
        have hch : ∀ (b : ↑(B₀ \ I)), ∃ Ib, Ib ⊆ I ∧ Ib.Finite ∧ ¬Indep (insert (b : α) Ib) := by
          rintro ⟨b, hb⟩; exact htofin I b hI (hcon b ⟨hB₀B hb.1, hb.2⟩)
        choose! f hf using hch
        have : Finite ↑(B₀ \ I) := hB₀fin.sdiff.to_subtype
        refine ⟨iUnion f ∪ (B₀ ∩ I),
          union_subset (iUnion_subset (fun i ↦ (hf i).1)) inter_subset_right,
          (finite_iUnion fun i ↦ (hf i).2.1).union (hB₀fin.subset inter_subset_left),
          fun x ⟨hxB₀, hxn⟩ hi ↦ ?_⟩
        have hxI : x ∉ I := fun hxI ↦ hxn <| Or.inr ⟨hxB₀, hxI⟩
        refine (hf ⟨x, ⟨hxB₀, hxI⟩⟩).2.2 (indep_subset hi <| insert_subset_insert ?_)
        apply subset_union_of_subset_left
        apply subset_iUnion

Goal state after:
case neg
α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∉ B
hcon : ∀ x ∈ B \ I, ¬Indep (insert x I)
heBdep : ¬Indep (insert e B)
B₀ : Set α
hB₀B : B₀ ⊆ B
hB₀fin : B₀.Finite
hB₀e : ¬Indep (insert e B₀)
hB₀ : Indep B₀
hexI₀ : ∃ I₀ ⊆ I, I₀.Finite ∧ ∀ x ∈ B₀ \ I₀, ¬Indep (insert x I₀)
⊢ False
Module: Mathlib.Combinatorics.Matroid.Basic

Goal state before:
pp: α : Type u_1
M : Matroid α
I J X : Set α
hI : M.IsBasis I X
hJ : M.Indep J
hIJ : I ⊆ J
⊢ M.IsBasis J (J ∪ X)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I X : Set α
e : α
hI : M.IsBasis I X
h : M.Indep (insert e I)
⊢ M.IsBasis (insert e I) (insert e X)

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
A : Type u_4
inst✝³ : CommSemiring R
inst✝² : CommSemiring A
inst✝¹ : Algebra R A
inst✝ : FaithfulSMul R A
M : Pic R
h : M ∈ relPic R A
e : A ⊗[R] M.AsModule ≃ₗ[A] A
f : A ⊗[R] M⁻¹.AsModule ≃ₗ[A] A
⊢ Pic.mk R (M.AsModule ⊗[R] M⁻¹.AsModule) = 1

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
B I X : Set α
hB : M.IsBase B
hBX : B ⊆ X
hIX : M.IsBasis I X
⊢ M.IsBase I

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
B I : Set α
hI : M.Indep I
hB : M.IsBase B
⊢ ∃ B', M.IsBase B' ∧ I ⊆ B' ∧ B' ⊆ I ∪ B

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
I J X : Set α
hI : M.IsBasis' I X
hIJ : I ⊆ J
hJ : M.Indep J
⊢ J ∩ X = I

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
B X : Set α
hX : X ⊆ M.E
hB : M.IsBase B
hBX : B ⊆ X
⊢ M.IsBasis B X

Tactic:
by

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

Goal state before:
pp: α : Type u_1
E : Set α
Indep : Set α → Prop
indep_empty : Indep ∅
indep_subset : ∀ ⦃I J : Set α⦄, Indep J → I ⊆ J → Indep I
indep_aug :
  ∀ ⦃I J : Set α⦄, Indep I → I.Finite → Indep J → J.Finite → I.ncard < J.ncard → ∃ e ∈ J, e ∉ I ∧ Indep (insert e I)
indep_compact : ∀ (I : Set α), (∀ J ⊆ I, J.Finite → Indep J) → Indep I
subset_ground : ∀ (I : Set α), Indep I → I ⊆ E
htofin : ∀ (I : Set α) (e : α), Indep I → ¬Indep (insert e I) → ∃ I₀ ⊆ I, I₀.Finite ∧ ¬Indep (insert e I₀)
I B : Set α
hI : Indep I
hImax : ¬Maximal Indep I
hBmax : Maximal Indep B
e : α
heI : e ∉ I
hins : Indep (insert e I)
heB : e ∉ B
hcon : ∀ x ∈ B \ I, ¬Indep (insert x I)
heBdep : ¬Indep (insert e B)
B₀ : Set α
hB₀B : B₀ ⊆ B
hB₀fin : B₀.Finite
hB₀e : ¬Indep (insert e B₀)
hB₀ : Indep B₀
I₀ : Set α
hI₀I : I₀ ⊆ I
hI₀fin : I₀.Finite
hI₀ : ∀ x ∈ B₀ \ I₀, ¬Indep (insert x I₀)
E₀ : Set α := insert e (I₀ ∪ B₀)
hE₀fin : E₀.Finite
⊢ {J | B₀ ⊆ J ∧ Indep J ∧ J ⊆ E₀} ⊆ {b | b ⊆ E₀}

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
X Y : Set α
hXY : X ⊆ Y
hY : Y ⊆ M.E
I I' : Set α
hI : M.IsBasis I X
hI' : M.IsBasis I' Y
hII' : I ⊆ I'
⊢ M.IsBasis (I ∪ I' \ I) Y

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M : Matroid α
X Y : Set α
hXY : X ⊆ Y
hY : Y ⊆ M.E
⊢ ∃ I J, M.IsBasis I X ∧ M.IsBasis (I ∪ J) Y ∧ Disjoint X J

Tactic:
by

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

Goal state before:
pp: α : Type u_1
E : Set α
hE : E.Finite
f : Matroid α → Set α × Set (Set α) := fun M ↦ (M.E, {B | M.IsBase B})
⊢ Function.Injective f

Tactic:
by

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

Goal state before:
pp: case h.refine_1
α : Type u_1
M✝ : Matroid α
I✝ B✝ X✝ : Set α
M : Matroid α
I X : Set α
hIE : I ⊆ M.E
B : Set α
hB : M.IsBase B
hIB : Disjoint I B
hI_not_max : ¬Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) I
hX_max : Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) X
hXE : X ⊆ M.E
B' : Set α := M.E \ X
hB' : M.IsBase B'
hX : B' = M.E \ X
hI : ¬M.IsBase (M.E \ I)
B'' : Set α
hB'' : M.IsBase B''
hB''₁ : B' \ I ⊆ B''
hB''₂ : B'' ⊆ B' ∪ B ∧ I ⊆ B''ᶜ
hssu : I ⊂ B''ᶜ ∩ M.E
e : α
heI : e ∉ I
heB'' : e ∉ B''
heE : e ∈ M.E
heX : e ∉ X
⊢ e ∈ B'

pp: case h.refine_2
α : Type u_1
M✝ : Matroid α
I✝ B✝ X✝ : Set α
M : Matroid α
I X : Set α
hIE : I ⊆ M.E
B : Set α
hB : M.IsBase B
hIB : Disjoint I B
hI_not_max : ¬Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) I
hX_max : Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) X
hXE : X ⊆ M.E
B' : Set α := M.E \ X
hB' : M.IsBase B'
hX : B' = M.E \ X
hI : ¬M.IsBase (M.E \ I)
B'' : Set α
hB'' : M.IsBase B''
hB''₁ : B' \ I ⊆ B''
hB''₂ : B'' ⊆ B' ∪ B ∧ I ⊆ B''ᶜ
hssu : I ⊂ B''ᶜ ∩ M.E
e : α
heI : e ∉ I
heB'' : e ∉ B''
heE : e ∈ M.E
⊢ Disjoint (insert e I) B''

Tactic:
· rw [hX]; exact ⟨heE, heX⟩

Goal state after:
case h.refine_2
α : Type u_1
M✝ : Matroid α
I✝ B✝ X✝ : Set α
M : Matroid α
I X : Set α
hIE : I ⊆ M.E
B : Set α
hB : M.IsBase B
hIB : Disjoint I B
hI_not_max : ¬Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) I
hX_max : Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) X
hXE : X ⊆ M.E
B' : Set α := M.E \ X
hB' : M.IsBase B'
hX : B' = M.E \ X
hI : ¬M.IsBase (M.E \ I)
B'' : Set α
hB'' : M.IsBase B''
hB''₁ : B' \ I ⊆ B''
hB''₂ : B'' ⊆ B' ∪ B ∧ I ⊆ B''ᶜ
hssu : I ⊂ B''ᶜ ∩ M.E
e : α
heI : e ∉ I
heB'' : e ∉ B''
heE : e ∈ M.E
⊢ Disjoint (insert e I) B''
Module: Mathlib.Combinatorics.Matroid.Basic

Goal state before:
pp: α : Type u_1
E : Set α
hE : E.Finite
⊢ {M | M.E ⊆ E}.Finite

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u
A : Type u_4
inst✝³ : CommSemiring R
inst✝² : CommSemiring A
inst✝¹ : Algebra R A
inst✝ : FaithfulSMul R A
⊢ (unitsToPic R A).range = relPic R A

Tactic:
by

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

Goal state before:
pp: α : Type u_1
E : Set α
hE : E.Finite
M : Matroid α
⊢ M ∈ {M | M.E = E} → M ∈ {M | M.E ⊆ E}

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M✝ : Matroid α
R✝ I✝ X Y : Set α
M : Matroid α
R I : Set α
hI : M.Indep I
hIY : I ⊆ R
hIn : ¬M.IsBasis I (R ∩ M.E)
B' : Set α
hB' : M.IsBase B'
hI' : M✶.IsBasis (M.E \ (B' ∪ R ∩ M.E)) (M.E \ (R ∩ M.E))
B : Set α
hB : M.IsBase B
hIB : I ⊆ B
hBIB' : B ⊆ I ∪ B'
⊢ M.E \ (B' ∪ R ∩ M.E) ⊆ M.E \ (B ∪ R ∩ M.E)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M✝ : Matroid α
R✝ I✝ X Y : Set α
M : Matroid α
R I : Set α
hI : M.Indep I
hIY : I ⊆ R
hIn : ¬M.IsBasis I (R ∩ M.E)
B' : Set α
hB' : M.IsBase B'
hI' : M✶.IsBasis (M.E \ (B' ∪ R ∩ M.E)) (M.E \ (R ∩ M.E))
B : Set α
hB : M.IsBase B
hIB : I ⊆ B
hBIB' : B ⊆ I ∪ B'
hss : M.E \ (B' ∪ R ∩ M.E) ⊆ M.E \ (B ∪ R ∩ M.E)
⊢ M✶.Indep (M.E \ (B ∪ R ∩ M.E))

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u_5
inst✝³ : CommRing R
inst✝² : IsFractionRing R R
I J : Ideal R
inst✝¹ : Module.Invertible R ↥I
inst✝ : Module.Invertible R ↥J
h : Pic.mk R (↥I ⊗[R] ↥J) = 1
e✝ : ↥I ⊗[R] ↥J ≃ₗ[R] R
e : R ≃ₗ[R] ↥(I * J)
⊢ IsRightRegular ↑(e 1)

Tactic:
by

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

Goal state before:
pp: α : Type u_1
M✝ : Matroid α
I B X : Set α
M : Matroid α
⊢ ∀ ⦃I B : Set α⦄,
    (I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) →
      ¬Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) I →
        Maximal (fun I ↦ I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint I B) B →
          ∃ x ∈ B \ I, insert x I ⊆ M.E ∧ ∃ B, M.IsBase B ∧ Disjoint (insert x I) B

Tactic:
by

Goal state after:
Module: Mathlib.RingTheory.PicardGroup

Goal state before:
pp: R : Type u_5
inst✝³ : CommRing R
inst✝² : IsFractionRing R R
I J : Ideal R
inst✝¹ : Module.Invertible R ↥I
inst✝ : Module.Invertible R ↥J
h : Pic.mk R (↥I ⊗[R] ↥J) = 1
⊢ I = ⊤ ∧ J = ⊤

Tactic:
by

Goal state after: