mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
h : ∀ (U : ℕ → Set E), (∀ (i : ℕ), IsOpen[inst✝] (U i)) → A ⊆ ⋃ i, U i → ∃ t, A ⊆ ⋃ i ∈ t, U i
⊢ IsCountablyCompact A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Bounded.ArzelaAscoli

Goal state before:
pp: α : Type u
β : Type v
inst✝³ : TopologicalSpace α
inst✝² : CompactSpace α
inst✝¹ : PseudoMetricSpace β
inst✝ : CompactSpace β
A : Set (α →ᵇ β)
closed : IsClosed A
H : ∀ (x₀ : α), ∀ ε > 0, ∃ U ∈ nhds x₀, ∀ x ∈ U, ∀ x' ∈ U, ∀ (i : ↑A), dist (↑i x) (↑i x') < ε
ε : ℝ
ε0 : ε > 0
ε₁ : ℝ
ε₁0 : 0 < ε₁
εε₁ : ε₁ < ε
ε₂ : ℝ := ε₁ / 2 / 2
ε₂0 : ε₂ > 0
U : α → Set α
hU : ∀ (x : α), x ∈ U x ∧ IsOpen (U x) ∧ ∀ y ∈ U x, ∀ z ∈ U x, ∀ {f : α →ᵇ β}, f ∈ A → dist (f y) (f z) < ε₂
tα : Set α
left✝¹ : tα ⊆ univ
hfin✝ : tα.Finite
htα : univ ⊆ ⋃ x ∈ tα, U x
val✝¹ : Fintype ↑tα
tβ : Set β
left✝ : tβ ⊆ univ
hfin : tβ.Finite
htβ : univ ⊆ ⋃ y ∈ tβ, ball y ε₂
val✝ : Fintype ↑tβ
F : β → β
hF : ∀ (y : β), F y ∈ tβ ∧ dist y (F y) < ε₂
f : α →ᵇ β
hf : f ∈ A
g : α →ᵇ β
hg : g ∈ A
f_eq_g : (fun f a ↦ ⟨F (↑f ↑a), ⋯⟩) ⟨f, hf⟩ = (fun f a ↦ ⟨F (↑f ↑a), ⋯⟩) ⟨g, hg⟩
x x' : α
x'tα : x' ∈ tα
hx' : x ∈ U x'
⊢ ε₂ + ε₂ + ε₁ / 2 = ε₁

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
b : Set ι
hb : b.Countable
U : ι → Set E
hUo : ∀ i ∈ b, IsOpen[inst✝] (U i)
hAU : A ⊆ ⋃ i ∈ b, U i
this : Countable ↑b
⊢ A ⊆ ⋃ i, U ↑i

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Bounded.ArzelaAscoli

Goal state before:
pp: α : Type u
β : Type v
inst✝³ : TopologicalSpace α
inst✝² : CompactSpace α
inst✝¹ : PseudoMetricSpace β
inst✝ : CompactSpace β
A : Set (α →ᵇ β)
closed : IsClosed A
H : Equicontinuous fun x ↦ ⇑↑x
⊢ IsCompact A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
b : Set ι
hb : b.Countable
U : ι → Set E
hUo : ∀ i ∈ b, IsOpen[inst✝] (U i)
hAU : A ⊆ ⋃ i ∈ b, U i
⊢ ∃ t ⊆ b, t.Finite ∧ A ⊆ ⋃ i ∈ t, U i

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
⊢ IsCountablyCompact A ↔
    ∀ (U : ℕ → Set E), (∀ (i : ℕ), IsOpen[inst✝] (U i)) → A ⊆ ⋃ i, U i → ∃ t, t.Finite ∧ A ⊆ ⋃ i ∈ t, U i

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Interval

Goal state before:
pp: α : Type u_1
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
a b c : α
inst✝² : Fact (a ≤ b)
inst✝¹ : Fact (b ≤ c)
E : Type u_2
inst✝ : TopologicalSpace E
f : C(↑(Icc a b), E)
g : C(↑(Icc b c), E)
ι : Type u_3
p : Filter ι
F : ι → C(↑(Icc a b), E)
G : ι → C(↑(Icc b c), E)
hfg : ∀ᶠ (i : ι) in p, (F i) ⊤ = (G i) ⊥
hfg' : f ⊤ = g ⊥
hf :
  ∀ (K : Set ↑(Icc a b)),
    IsCompact K → ∀ (U : Set E), IsOpen[inst✝] U → MapsTo (⇑f) K U → ∀ᶠ (a_4 : ι) in p, MapsTo (⇑(F a_4)) K U
hg :
  ∀ (K : Set ↑(Icc b c)),
    IsCompact K → ∀ (U : Set E), IsOpen[inst✝] U → MapsTo (⇑g) K U → ∀ᶠ (a : ι) in p, MapsTo (⇑(G a)) K U
K : Set ↑(Icc a c)
hK : IsCompact K
U : Set E
hU : IsOpen[inst✝] U
hfgU : MapsTo (⇑(f.concat g)) K U
h : b ∈ Icc a c
K₁ : Set ↑(Icc a b) := ⇑projIccCM '' Subtype.val '' (K ∩ Iic ⟨b, h⟩)
K₂ : Set ↑(Icc b c) := ⇑projIccCM '' Subtype.val '' (K ∩ Ici ⟨b, h⟩)
hK₁ : IsCompact K₁
hK₂ : IsCompact K₂
⊢ MapsTo (⇑f) K₁ U

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsSeqCompact A
x : ℕ → E
hx : ∀ᶠ (n : ℕ) in atTop, x n ∈ A
⊢ ∃ a ∈ A, MapClusterPt a atTop x

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
F : Type u_3
inst✝¹ : TopologicalSpace E
inst✝ : TopologicalSpace F
A : Set E
hA : IsCountablyCompact A
f : E → F
hf : Continuous[inst✝¹, inst✝] f
l : Filter F
hl_nebot : l.NeBot
hl_count : l.IsCountablyGenerated
⊢ l ≤ 𝓟 (f '' A) → ∃ a ∈ f '' A, ClusterPt a l

Tactic:
hle

Goal state after:
E : Type u_2
F : Type u_3
inst✝¹ : TopologicalSpace E
inst✝ : TopologicalSpace F
A : Set E
hA : IsCountablyCompact A
f : E → F
hf : Continuous[inst✝¹, inst✝] f
l : Filter F
hl_nebot : l.NeBot
hl_count : l.IsCountablyGenerated
hle : l ≤ 𝓟 (f '' A)
⊢ ∃ a ∈ f '' A, ClusterPt a l
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
F : Type u_3
inst✝¹ : TopologicalSpace E
inst✝ : TopologicalSpace F
A : Set E
hA : IsCountablyCompact A
f : E → F
hf : Continuous[inst✝¹, inst✝] f
⊢ IsCountablyCompact (f '' A)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
F : Type u_3
inst✝¹ : TopologicalSpace E
inst✝ : TopologicalSpace F
A : Set E
f : E → F
hf : IsInducing f
⊢ IsCountablyCompact A ↔ IsCountablyCompact (f '' A)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
⊢ IsCountablyCompact A ↔ IsCountablyCompact univ

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : TopologicalSpace E
inst✝² : TopologicalSpace F
A✝ B : Set E
inst✝¹ : SequentialSpace E
inst✝ : CountablyCompactSpace E
x : ℕ → E
hx : ∀ (x_1 : E) (x_2 : ℕ → ℕ), StrictMono x_2 → ¬Tendsto (x ∘ x_2) atTop (𝓝 x_1)
A : Set E := ⋃ i, closure[inst✝³] {x i}
this : IsCountablyCompact A
⊢ ∃ a ∈ A, MapClusterPt a atTop x

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Bounded.ArzelaAscoli

Goal state before:
pp: α : Type u
β : Type v
inst✝² : TopologicalSpace α
inst✝¹ : CompactSpace α
inst✝ : PseudoMetricSpace β
s : Set β
hs : IsCompact s
A : Set (α →ᵇ β)
closed : IsClosed A
in_s : ∀ (f : α →ᵇ β) (x : α), f ∈ A → f x ∈ s
H : Equicontinuous fun x ↦ ⇑↑x
⊢ IsCompact A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Interval

Goal state before:
pp: α : Type u_1
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
a b c : α
inst✝² : Fact (a ≤ b)
inst✝¹ : Fact (b ≤ c)
E : Type u_2
inst✝ : TopologicalSpace E
f : C(↑(Icc a b), E)
g : C(↑(Icc b c), E)
ι : Type u_3
p : Filter ι
F : ι → C(↑(Icc a b), E)
G : ι → C(↑(Icc b c), E)
hfg : ∀ᶠ (i : ι) in p, (F i) ⊤ = (G i) ⊥
hfg' : f ⊤ = g ⊥
hf :
  ∀ (K : Set ↑(Icc a b)),
    IsCompact K → ∀ (U : Set E), IsOpen[inst✝] U → MapsTo (⇑f) K U → ∀ᶠ (a_4 : ι) in p, MapsTo (⇑(F a_4)) K U
hg :
  ∀ (K : Set ↑(Icc b c)),
    IsCompact K → ∀ (U : Set E), IsOpen[inst✝] U → MapsTo (⇑g) K U → ∀ᶠ (a : ι) in p, MapsTo (⇑(G a)) K U
K : Set ↑(Icc a c)
hK : IsCompact K
U : Set E
hU : IsOpen[inst✝] U
hfgU : MapsTo (⇑(f.concat g)) K U
h : b ∈ Icc a c
K₁ : Set ↑(Icc a b) := ⇑projIccCM '' Subtype.val '' (K ∩ Iic ⟨b, h⟩)
K₂ : Set ↑(Icc b c) := ⇑projIccCM '' Subtype.val '' (K ∩ Ici ⟨b, h⟩)
hK₁ : IsCompact K₁
hK₂ : IsCompact K₂
hfU : MapsTo (⇑f) K₁ U
⊢ MapsTo (⇑g) K₂ U

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.LocallyConstant

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝³ : TopologicalSpace X
inst✝² : TopologicalSpace Y
inst✝¹ : Monoid Y
inst✝ : ContinuousMul Y
⊢ ↑1 = 1

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.LocallyConstant

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝³ : TopologicalSpace X
inst✝² : TopologicalSpace Y
inst✝¹ : Monoid Y
inst✝ : ContinuousMul Y
x y : LocallyConstant X Y
⊢ ↑(x * y) = ↑x * ↑y

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.LocallyConstant

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝⁶ : TopologicalSpace X
inst✝⁵ : TopologicalSpace Y
R : Type u_3
inst✝⁴ : Semiring R
inst✝³ : AddCommMonoid Y
inst✝² : Module R Y
inst✝¹ : ContinuousAdd Y
inst✝ : ContinuousConstSMul R Y
x : R
y : LocallyConstant X Y
⊢ ↑(x • y) = (RingHom.id R) x • ↑y

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.LocallyConstant

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝⁵ : TopologicalSpace X
inst✝⁴ : TopologicalSpace Y
R : Type u_3
inst✝³ : CommSemiring R
inst✝² : Semiring Y
inst✝¹ : Algebra R Y
inst✝ : IsTopologicalSemiring Y
r : R
⊢ ↑((algebraMap R (LocallyConstant X Y)) r) = (algebraMap R C(X, Y)) r

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.LocallyConstant

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝⁷ : TopologicalSpace X
inst✝⁶ : TopologicalSpace Y
R : Type u_3
inst✝⁵ : CommSemiring R
inst✝⁴ : TotallySeparatedSpace X
inst✝³ : Semiring Y
inst✝² : Algebra R Y
inst✝¹ : IsTopologicalSemiring Y
inst✝ : Nontrivial Y
x✝¹ x✝ : X
hxy : x✝¹ ≠ x✝
w✝ : Set X
hU : IsClopen w✝
left✝ : x✝¹ ∈ w✝
right✝ : x✝ ∈ w✝ᶜ
⊢ ⇑(charFn Y hU) ∈ (fun f ↦ ⇑f) '' ↑(toContinuousMapAlgHom R).range ∧ (charFn Y hU) x✝¹ ≠ (charFn Y hU) x✝

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.LocallyConvex

Goal state before:
pp: X : Type u_1
𝕜 : Type u_2
E : Type u_3
inst✝⁸ : TopologicalSpace X
inst✝⁷ : Semiring 𝕜
inst✝⁶ : PartialOrder 𝕜
inst✝⁵ : AddCommGroup E
inst✝⁴ : Module 𝕜 E
inst✝³ : TopologicalSpace E
inst✝² : LocallyConvexSpace 𝕜 E
inst✝¹ : IsTopologicalAddGroup E
inst✝ : ContinuousConstSMul 𝕜 E
⊢ ∀ (i : Set X × Set E), IsCompact i.1 ∧ i.2 ∈ 𝓝 0 ∧ Convex 𝕜 i.2 → Convex 𝕜 {f | Set.MapsTo (⇑f) i.1 (id i.2)}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : TopologicalSpace E
inst✝² : TopologicalSpace F
A✝ B : Set E
inst✝¹ : SequentialSpace E
inst✝ : CountablyCompactSpace E
x : ℕ → E
hx : ∀ (x_1 : E) (x_2 : ℕ → ℕ), StrictMono x_2 → ¬Tendsto (x ∘ x_2) atTop (𝓝 x_1)
A : Set E := ⋃ i, closure[inst✝³] {x i}
this : IsCountablyCompact A
a : E
ha : a ∈ A ∧ MapClusterPt a atTop x
⊢ ∃ k, ∀ n > k, a ∉ closure[inst✝³] {x n}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : TopologicalSpace E
inst✝² : TopologicalSpace F
A✝ B : Set E
inst✝¹ : SequentialSpace E
inst✝ : CountablyCompactSpace E
x : ℕ → E
hx : ∀ (x_1 : E) (x_2 : ℕ → ℕ), StrictMono x_2 → ¬Tendsto (x ∘ x_2) atTop (𝓝 x_1)
A : Set E := ⋃ i, closure[inst✝³] {x i}
this : IsCountablyCompact A
a : E
ha : a ∈ A ∧ MapClusterPt a atTop x
k : ℕ
hk : ∀ n > k, a ∉ closure[inst✝³] {x n}
⊢ a ∉ ⋃ i, closure[inst✝³] {x (i + (k + 1))}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
S : Set (Set X)
T : Set (Set Y)
hS₁ : ∀ K ∈ S, IsCompact K
hT : IsTopologicalBasis T
hS₂ : ∀ (f : C(X, Y)) (x : X), ∀ V ∈ T, f x ∈ V → ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
f : C(X, Y)
K : Set X
hK : IsCompact K
U : Set Y
hU : IsOpen[inst✝] U
hfKU : MapsTo (⇑f) K U
⊢ ∃ t ⊆ T, t.Finite ∧ (∀ V ∈ t, V ⊆ U) ∧ ⇑f '' K ⊆ ⋃₀ t

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
F : Type u_3
inst✝³ : TopologicalSpace E
inst✝² : TopologicalSpace F
A B : Set E
inst✝¹ : SequentialSpace E
inst✝ : CountablyCompactSpace E
⊢ SeqCompactSpace E

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
S : Set (Set X)
T : Set (Set Y)
hS₁ : ∀ K ∈ S, IsCompact K
hT : IsTopologicalBasis T
hS₂ : ∀ (f : C(X, Y)) (x : X), ∀ V ∈ T, f x ∈ V → ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
f : C(X, Y)
K : Set X
hK : IsCompact K
U : Set Y
hU : IsOpen[inst✝] U
hfKU : MapsTo (⇑f) K U
t : Set (Set Y)
htT : t ⊆ T
htf : t.Finite
hTU : ∀ V ∈ t, V ⊆ U
hKT : K ⊆ ⇑f ⁻¹' ⋃₀ t
⊢ ∀ x ∈ K, ∃ L ∈ S, L ∈ 𝓝 x ∧ MapsTo (⇑f) L (⋃₀ t)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
F : Type u_3
inst✝¹ : TopologicalSpace E
inst✝ : TopologicalSpace F
A : Set E
f : E → F
hf : IsInducing f
hA : IsSeqCompact A
x : ℕ → F
hx : ∀ (n : ℕ), x n ∈ f '' A
⊢ ∃ a ∈ f '' A, ∃ φ, StrictMono φ ∧ Tendsto (x ∘ φ) atTop (𝓝 a)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
F : Type u_3
inst✝¹ : TopologicalSpace E
inst✝ : TopologicalSpace F
A : Set E
f : E → F
hf : IsInducing f
hA : IsSeqCompact (f '' A)
x : ℕ → E
hx : ∀ (n : ℕ), x n ∈ A
⊢ ∃ a ∈ A, ∃ φ, StrictMono φ ∧ Tendsto (x ∘ φ) atTop (𝓝 a)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
⊢ IsSeqCompact A ↔ IsSeqCompact univ

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A B : Set E
hA : IsCountablyCompact A
hBA : B ⊆ A
hB : B.Infinite
⊢ ∃ a ∈ A, AccPt a (𝓟 B)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝¹ : TopologicalSpace E
inst✝ : T1Space E
A : Set E
h : ∀ B ⊆ A, B.Infinite → ∃ a ∈ A, AccPt a (𝓟 B)
x : ℕ → E
hx : ∀ᶠ (n : ℕ) in cofinite, x n ∈ A
hfin : (range x).Finite
this : ∃ a ∈ range x ∩ A, MapClusterPt a cofinite x
⊢ ∃ a ∈ A, MapClusterPt a cofinite x

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝¹ : TopologicalSpace E
inst✝ : T1Space E
A : Set E
h : ∀ B ⊆ A, B.Infinite → ∃ a ∈ A, AccPt a (𝓟 B)
x : ℕ → E
hx : ∀ᶠ (n : ℕ) in cofinite, x n ∈ A
hfin : (range x).Finite
⊢ ∀ᶠ (x_1 : ℕ) in cofinite, x x_1 ∈ A → x x_1 ∈ range x ∩ A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
S : Set (Set X)
T : Set (Set Y)
hS₁ : ∀ K ∈ S, IsCompact K
hT : IsTopologicalBasis T
hS₂ : ∀ (f : C(X, Y)) (x : X), ∀ V ∈ T, f x ∈ V → ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
f : C(X, Y)
K : Set X
hK : IsCompact K
U : Set Y
hU : IsOpen[inst✝] U
hfKU : MapsTo (⇑f) K U
t : Set (Set Y)
htT : t ⊆ T
htf : t.Finite
hTU : ∀ V ∈ t, V ⊆ U
hKT : K ⊆ ⇑f ⁻¹' ⋃₀ t
L : X → Set X
hLS : ∀ x ∈ K, L x ∈ S
hLmem : ∀ x ∈ K, L x ∈ 𝓝 x
hLt : ∀ x ∈ K, MapsTo (⇑f) (L x) (⋃₀ t)
s : Finset X
hsK : ∀ x ∈ s, x ∈ K
hs : K ⊆ ⋃ x ∈ s, L x
⊢ K ⊆ ⋃₀ (L '' ↑s)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝¹ : TopologicalSpace E
inst✝ : T1Space E
A : Set E
h : ∀ B ⊆ A, B.Infinite → ∃ a ∈ A, AccPt a (𝓟 B)
x : ℕ → E
hx : {a | x a ∉ A}.Finite
hfin : (range x).Infinite
⊢ range x \ A ⊆ x '' {a | x a ∉ A}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝¹ : TopologicalSpace E
inst✝ : T1Space E
A : Set E
h : ∀ B ⊆ A, B.Infinite → ∃ a ∈ A, AccPt a (𝓟 B)
x : ℕ → E
hx : ∀ᶠ (n : ℕ) in cofinite, x n ∈ A
hfin : (range x).Infinite
⊢ (range x ∩ A).Infinite

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Category.Profinite.Nobeling.Successor

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
hC : IsClosed C
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
l : ↑(MaxProducts C ho)
h₁ : ⊤ ≤ Submodule.span ℤ (Set.range (eval (π C fun x ↦ ord I x < o)))
⊢ Products.isGood (C' C ho) (↑l).Tail

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝¹ : TopologicalSpace E
inst✝ : T1Space E
A : Set E
h : ∀ B ⊆ A, B.Infinite → ∃ a ∈ A, AccPt a (𝓟 B)
x : ℕ → E
hx : ∀ᶠ (n : ℕ) in cofinite, x n ∈ A
hfin : (range x).Infinite
a : E
haA : a ∈ A
hacc : AccPt a (𝓟 (range x ∩ A))
s : Set E
hs : s ∈ 𝓝 a
⊢ s ∩ (range x ∩ A) ⊆ x '' {a | x a ∈ s}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝¹ : TopologicalSpace E
inst✝ : T1Space E
A : Set E
h : ∀ B ⊆ A, B.Infinite → ∃ a ∈ A, AccPt a (𝓟 B)
⊢ IsCountablyCompact A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: case pos
E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
hl : IsLindelof A
ι : Type u_2
U : ι → Set E
hUo : ∀ (i : ι), IsOpen[inst✝] (U i)
hAU : A ⊆ ⋃ i, U i
h : Nonempty ι
⊢ ∃ t, A ⊆ ⋃ i ∈ t, U i

Tactic:
obtain ⟨f, hf⟩ := hl.indexed_countable_subcover U hUo hAU

Goal state after:
case pos
E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
hl : IsLindelof A
ι : Type u_2
U : ι → Set E
hUo : ∀ (i : ι), IsOpen[inst✝] (U i)
hAU : A ⊆ ⋃ i, U i
h : Nonempty ι
f : ℕ → ι
hf : A ⊆ ⋃ n, U (f n)
⊢ ∃ t, A ⊆ ⋃ i ∈ t, U i
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
hl : IsLindelof A
ι : Type u_2
U : ι → Set E
hUo : ∀ (i : ι), IsOpen[inst✝] (U i)
hAU : A ⊆ ⋃ i, U i
h : Nonempty ι
f : ℕ → ι
hf : A ⊆ ⋃ n, U (f n)
t : Finset ℕ
ht : A ⊆ ⋃ i ∈ t, (U ∘ f) i
⊢ A ⊆ ⋃ i ∈ Finset.image f t, U i

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Category.Profinite.Nobeling.Successor

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
hC : IsClosed C
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
h₁ : ⊤ ≤ Submodule.span ℤ (Set.range (eval (π C fun x ↦ ord I x < o)))
⊢ Function.Injective (MaxToGood C hC hsC ho h₁)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
hl : IsLindelof A
ι : Type u_2
U : ι → Set E
hUo : ∀ (i : ι), IsOpen[inst✝] (U i)
hAU : A ⊆ ⋃ i, U i
h : IsEmpty ι
⊢ A ⊆ ⋃ i ∈ ∅, U i

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A : Set E
hA : IsCountablyCompact A
hl : IsLindelof A
⊢ IsCompact A

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
S : Set (Set X)
T : Set (Set Y)
hS₁ : ∀ K ∈ S, IsCompact K
hT : IsTopologicalBasis T
hS₂ : ∀ (f : C(X, Y)) (x : X), ∀ V ∈ T, f x ∈ V → ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
f : C(X, Y)
K : Set X
hK : IsCompact K
U : Set Y
hU : IsOpen[inst✝] U
hfKU : MapsTo (⇑f) K U
t : Set (Set Y)
htT : t ⊆ T
htf : t.Finite
hTU : ∀ V ∈ t, V ⊆ U
hKT : K ⊆ ⇑f ⁻¹' ⋃₀ t
⊢ ∃ s ⊆ S, s.Finite ∧ K ⊆ ⋃₀ s ∧ MapsTo (⇑f) (⋃₀ s) (⋃₀ t)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
S : Set (Set X)
T : Set (Set Y)
hS₁ : ∀ K ∈ S, IsCompact K
hT : IsTopologicalBasis T
hS₂ : ∀ (f : C(X, Y)) (x : X), ∀ V ∈ T, f x ∈ V → ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
f : C(X, Y)
K : Set X
hK : IsCompact K
U : Set Y
hU : IsOpen[inst✝] U
hfKU : MapsTo (⇑f) K U
t : Set (Set Y)
htT : t ⊆ T
htf : t.Finite
hTU : ∀ V ∈ t, V ⊆ U
hKT : K ⊆ ⇑f ⁻¹' ⋃₀ t
s : Set (Set X)
hsS : s ⊆ S
hsf : s.Finite
hKs : K ⊆ ⋃₀ s
hst : MapsTo (⇑f) (⋃₀ s) (⋃₀ t)
⊢ ⋂ L ∈ s, {g | MapsTo (⇑g) L (⋃₀ t)} ⊆ {g | MapsTo (⇑g) K U}

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Category.Profinite.Nobeling.Successor

Goal state before:
pp: I : Type u
C : Set (I → Bool)
inst✝¹ : LinearOrder I
inst✝ : WellFoundedLT I
o : Ordinal.{u}
hC : IsClosed C
hsC : contained C (Order.succ o)
ho : o < Ordinal.type fun x1 x2 ↦ x1 < x2
h₁ : ⊤ ≤ Submodule.span ℤ (Set.range (eval (π C fun x ↦ ord I x < o)))
⊢ LinearIndependent ℤ (eval (C' C ho)) →
    LinearIndependent (ι := ↑(MaxProducts C ho)) ℤ
      (⇑(ConcreteCategory.hom (ModuleCat.ofHom (Linear_CC' C hsC ho))) ∘ SumEval C ho ∘ Sum.inr)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A B : Set E
hA : ∀ (U : ℕ → Set E), (∀ (i : ℕ), IsOpen[inst✝] (U i)) → A ⊆ ⋃ i, U i → ∃ t, t.Finite ∧ A ⊆ ⋃ i ∈ t, U i
hB : ∀ (U : ℕ → Set E), (∀ (i : ℕ), IsOpen[inst✝] (U i)) → B ⊆ ⋃ i, U i → ∃ t, t.Finite ∧ B ⊆ ⋃ i ∈ t, U i
U : ℕ → Set E
hUo : ∀ (i : ℕ), IsOpen[inst✝] (U i)
hAU : A ∪ B ⊆ ⋃ i, U i
t₁ : Set ℕ
ht₁ : t₁.Finite
hA_sub : A ⊆ ⋃ k ∈ t₁, U k
t₂ : Set ℕ
ht₂ : t₂.Finite
hB_sub : B ⊆ ⋃ k ∈ t₂, U k
⊢ (⋃ k ∈ t₁, U k) ∪ ⋃ k ∈ t₂, U k = ⋃ k ∈ t₁ ∪ t₂, U k

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
A B : Set E
hA : IsCountablyCompact A
hB : IsCountablyCompact B
⊢ IsCountablyCompact (A ∪ B)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
inst✝ : TopologicalSpace E
s : Finset ι
f : ι → Set E
hf : ∀ i ∈ s, IsCountablyCompact (f i)
⊢ IsCountablyCompact (⋃ i ∈ s, f i)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
inst✝ : TopologicalSpace E
s : Set ι
f : ι → Set E
hs : s.Finite
hf : ∀ i ∈ s, IsCountablyCompact (f i)
s' : Finset ι := hs.toFinset
⊢ ⋃ i ∈ s, f i = ⋃ i ∈ s', f i

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: ι : Type u_1
E : Type u_2
inst✝ : TopologicalSpace E
s : Set ι
f : ι → Set E
hs : s.Finite
hf : ∀ i ∈ s, IsCountablyCompact (f i)
⊢ IsCountablyCompact (⋃ i ∈ s, f i)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝¹ : TopologicalSpace X
inst✝ : TopologicalSpace Y
S : Set (Set X)
T : Set (Set Y)
hS₁ : ∀ K ∈ S, IsCompact K
hT : IsTopologicalBasis T
hS₂ : ∀ (f : C(X, Y)) (x : X), ∀ V ∈ T, f x ∈ V → ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
⊢ compactOpen = generateFrom (image2 (fun K t ↦ {f | MapsTo (⇑f) K (⋃₀ t)}) S {t | t.Finite ∧ t ⊆ T})

Tactic:
by

Goal state after:
Module: Mathlib.Topology.Compactness.CountablyCompact

Goal state before:
pp: E : Type u_2
inst✝ : TopologicalSpace E
S : Set (Set E)
hf : S.Finite
hc : ∀ s ∈ S, IsCountablyCompact s
⊢ IsCountablyCompact (⋃₀ S)

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Interval

Goal state before:
pp: α : Type u_1
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
a b c : α
inst✝² : Fact (a ≤ b)
inst✝¹ : Fact (b ≤ c)
E : Type u_2
inst✝ : TopologicalSpace E
f : C(↑(Icc a b), E)
g : C(↑(Icc b c), E)
ι : Type u_3
p : Filter ι
F : ι → C(↑(Icc a b), E)
G : ι → C(↑(Icc b c), E)
hfg : ∀ᶠ (i : ι) in p, (F i) ⊤ = (G i) ⊥
hfg' : f ⊤ = g ⊥
hf : Tendsto F p (𝓝 f)
hg : Tendsto G p (𝓝 g)
⊢ Tendsto (fun i ↦ (F i).concat (G i)) p (𝓝 (f.concat g))

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Sigma

Goal state before:
pp: X : Type u_1
ι : Type u_2
Y : ι → Type u_3
inst✝² : TopologicalSpace X
inst✝¹ : (i : ι) → TopologicalSpace (Y i)
inst✝ : Nonempty X
⊢ Function.Injective fun g ↦ (sigmaMk g.fst).comp g.snd

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.SecondCountableSpace

Goal state before:
pp: X : Type u_1
Y : Type u_2
inst✝² : TopologicalSpace X
inst✝¹ : TopologicalSpace Y
inst✝ : SecondCountableTopology Y
hX :
  ∃ S,
    S.Countable ∧
      (∀ K ∈ S, IsCompact K) ∧
        ∀ (f : C(X, Y)) (V : Set Y), IsOpen[inst✝¹] V → ∀ x ∈ ⇑f ⁻¹' V, ∃ K ∈ S, K ∈ 𝓝 x ∧ MapsTo (⇑f) K V
⊢ ∃ b, b.Countable ∧ compactOpen = generateFrom b

Tactic:
by

Goal state after:
Module: Mathlib.Topology.ContinuousMap.Interval

Goal state before:
pp: α : Type u_1
inst✝⁵ : LinearOrder α
inst✝⁴ : TopologicalSpace α
inst✝³ : OrderTopology α
a b c : α
inst✝² : Fact (a ≤ b)
inst✝¹ : Fact (b ≤ c)
E : Type u_2
inst✝ : TopologicalSpace E
f : C(↑(Icc a b), E)
g : C(↑(Icc b c), E)
⊢ Continuous fun fg ↦ (↑fg).1.concat (↑fg).2

Tactic:
by

Goal state after: