awhecmu/canonical-drafter-extract-mathlib huggingface dataset:
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
Idist_v : ∀ a ∈ v, dist (c a) x ≤ r a + R x
R0 : ℝ := sSup (r '' v)
R0_def : R0 = sSup (r '' v)
R0_bdd : BddAbove (r '' v)
H : R x ≤ R0
R0pos : 0 < R0
vnonempty : v.Nonempty
a : ι
hav : a ∈ v
R0a : R0 / 2 < r a
b : ι
bu : b ∈ u
hbx : (B b ∩ ball x (R x)).Nonempty
⊢ r b ≤ R0

Tactic:
have : r b ≤ R0 := le_csSup R0_bdd (mem_image_of_mem _ ⟨bu, hbx⟩)
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
Idist_v : ∀ a ∈ v, dist (c a) x ≤ r a + R x
R0 : ℝ := sSup (r '' v)
R0_def : R0 = sSup (r '' v)
R0_bdd : BddAbove (r '' v)
H : R x ≤ R0
R0pos : 0 < R0
vnonempty : v.Nonempty
a : ι
hav : a ∈ v
R0a : R0 / 2 < r a
b : ι
bu : b ∈ u
hbx : (B b ∩ ball x (R x)).Nonempty
this : r b ≤ R0
linarith : 8 * R0 < r b + dist (c b) x → 2 / 2 = 1
linarith₁ : 8 * R0 < r b + dist (c b) x → HMul.hMul (α := ℝ) 1 2 = 2
linarith₂ : 8 * R0 < r b + dist (c b) x → GT.gt (α := ℝ) 2 0
linarith₃ :
  8 * R0 < r b + dist (c b) x →
    R x - R0 + 5 * (0 - R0) + 2 * (r b - R0) + (8 * R0 - (r b + dist (c b) x)) + (dist (c b) x - (r b + R x)) = 0
linarith₄ : 8 * R0 < r b + dist (c b) x → GT.gt (α := ℝ) 5 0
linarith₅ : 8 * R0 < r b + dist (c b) x → GT.gt (α := ℝ) 2 0
⊢ r b + dist (c b) x ≤ 8 * R0

Tactic:
linarith [Idist_v b ⟨bu, hbx⟩]

Premises used: And.intro
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
⊢ ∃ u_1 ∈ 𝓝[s \ ⋃ a ∈ u, B a] x, Eq (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) u_1 : ℝ≥0∞) (0 : ℝ≥0∞)

Tactic:
⟨_ ∩ ball x (R x), inter_mem_nhdsWithin _ (ball_mem_nhds _ (hR0 _)),
    nonpos_iff_eq_zero.mp (le_of_forall_gt_imp_ge_of_dense fun ε εpos => ?_)⟩

Premises used: inter_mem_nhdsWithin, Metric.ball, Inter.inter, Metric.ball_mem_nhds, And.intro, Exists.intro, Iff.mp, le_of_forall_gt_imp_ge_of_dense, nonpos_iff_eq_zero
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
refine : ∀ (ε : ℝ≥0∞) (εpos : 0 < ε), (μ : (a : Set α) → ℝ≥0∞) ((s \ ⋃ a ∈ u, B a) ∩ ball x (R x)) ≤ ε
⊢ ∃ u_1 ∈ 𝓝[s \ ⋃ a ∈ u, B a] x, Eq (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) u_1 : ℝ≥0∞) (0 : ℝ≥0∞)

Tactic:
refine ⟨_ ∩ ball x (R x), inter_mem_nhdsWithin _ (ball_mem_nhds _ (hR0 _)),
    nonpos_iff_eq_zero.mp (le_of_forall_gt_imp_ge_of_dense fun ε εpos => ?_)⟩
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
rw : v.PairwiseDisjoint B
⊢ Eq (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι)) : ℝ≥0∞)
    ((μ : (a : Set α) → ℝ≥0∞) (⋃ a ∈ v, B a) : ℝ≥0∞)

Tactic:
rw [measure_biUnion (u_count.mono vu) _ fun a ha => (h't _ (vu.trans ut ha)).measurableSet]

Premises used: MeasureTheory.measure_biUnion, HasSubset.Subset.trans, IsClosed.measurableSet, Set.Countable.mono
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
⊢ v.PairwiseDisjoint B

Tactic:
u_disj.subset vu

Premises used: Set.PairwiseDisjoint.subset
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
⊢ v.PairwiseDisjoint B

Tactic:
exact u_disj.subset vu

Premises used: Set.PairwiseDisjoint.subset
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
⊢ LE.le (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (⋃ a ∈ v, B a) : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞)

Tactic:
(measure_mono (iUnion₂_subset fun a ha => hK a (vu ha) ha.2))

Premises used: Set.iUnion₂_subset, And.right, MeasureTheory.measure_mono
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
⊢ LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)

Tactic:
μK
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
a :
  Eq (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι)) : ℝ≥0∞)
    ((μ : (a : Set α) → ℝ≥0∞) (⋃ a ∈ v, B a) : ℝ≥0∞)
⊢ LT.lt (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι))) ∞

Tactic:
calc
      (∑' a : v, μ (B a)) = μ (⋃ a ∈ v, B a) := by
        rw [measure_biUnion (u_count.mono vu) _ fun a ha => (h't _ (vu.trans ut ha)).measurableSet]
        exact u_disj.subset vu
      _ ≤ μ (closedBall x K) := (measure_mono (iUnion₂_subset fun a ha => hK a (vu ha) ha.2))
      _ < ∞ := μK

Premises used: Set.iUnion₂_subset, And.right, tsum, MeasureTheory.measure_mono, Metric.closedBall, Subtype.val, DFunLike.coe, Set.iUnion, SummationFilter.unconditional
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
⊢ LT.lt (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι))) ∞

Tactic:
have I : (∑' a : v, μ (B a)) < ∞ := by
    calc
      (∑' a : v, μ (B a)) = μ (⋃ a ∈ v, B a) := by
        rw [measure_biUnion (u_count.mono vu) _ fun a ha => (h't _ (vu.trans ut ha)).measurableSet]
        exact u_disj.subset vu
      _ ≤ μ (closedBall x K) := (measure_mono (iUnion₂_subset fun a ha => hK a (vu ha) ha.2))
      _ < ∞ := μK
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
I : LT.lt (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι))) ∞
⊢ 0 < ε / (↑C : ℝ≥0∞)

Tactic:
simp only [ENNReal.div_pos_iff, εpos.ne', ENNReal.coe_ne_top, Ne, not_false_iff,
        and_self_iff]

Premises used: ENNReal.div_pos_iff, Ne, LT.lt.ne', and_self_iff, not_false_iff, ENNReal.coe_ne_top
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
I : LT.lt (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι))) ∞
obtain :
  ∀ (w : Finset (↑v : Type u_2))
    (hw :
      ∑' (a : { a : (↑v : Type u_2) // a ∉ w }), (μ : (a : Set α) → ℝ≥0∞) (B (↑(↑a : (↑v : Type u_2)) : ι)) <
        ε / (↑C : ℝ≥0∞)),
    (μ : (a : Set α) → ℝ≥0∞) ((s \ ⋃ a ∈ u, B a) ∩ ball x (R x)) ≤ ε
⊢ (μ : (a : Set α) → ℝ≥0∞) ((s \ ⋃ a ∈ u, B a) ∩ ball x (R x)) ≤ ε

Tactic:
obtain ⟨w, hw⟩ : ∃ w : Finset v, (∑' a : { a // a ∉ w }, μ (B a)) < ε / C :=
    haveI : 0 < ε / C := by
      simp only [ENNReal.div_pos_iff, εpos.ne', ENNReal.coe_ne_top, Ne, not_false_iff,
        and_self_iff]
    ((tendsto_order.1 (ENNReal.tendsto_tsum_compl_atTop_zero I.ne)).2 _ this).exists

Premises used: ENNReal.ofNNReal, Finset, ENNReal.tendsto_tsum_compl_atTop_zero, tendsto_order, Set.Elem, HDiv.hDiv, Filter.Eventually.exists, And.right, Iff.mp, LT.lt.ne
-- Module: Mathlib.MeasureTheory.Covering.Vitali
Goal:
α : Type u_1
ι : Type u_2
inst : PseudoMetricSpace α
inst_1 : MeasurableSpace α
inst_2 : OpensMeasurableSpace α
inst_3 : SecondCountableTopology α
μ : Measure α
inst_4 : IsLocallyFiniteMeasure μ
s : Set α
t : Set ι
C : ℝ≥0
r : ι → ℝ
c : ι → α
B : ι → Set α
hB : ∀ a ∈ t, B a ⊆ closedBall (c a) (r a)
μB :
  ∀ a ∈ t,
    (μ : (a : Set α) → ℝ≥0∞) (closedBall (c a) (3 * r a)) ≤
      HMul.hMul (β := ℝ≥0∞) (↑C : ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (B a) : ℝ≥0∞)
ht : ∀ a ∈ t, (interior (B a)).Nonempty
h't : ∀ a ∈ t, IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] (B a)
hf : ∀ x ∈ s, ∀ ε > 0, ∃ a ∈ t, r a ≤ ε ∧ c a = x
R : (x : α) → ℝ
hR0 : ∀ (x : α), 0 < R x
hR1 : ∀ (x : α), R x ≤ 1
hRμ : ∀ (x : α), LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x (20 * R x)) : ℝ≥0∞) (∞ : ℝ≥0∞)
t' : Set ι := {a : ι | a ∈ t ∧ r a ≤ R (c a)}
u : Set ι
ut' : u ⊆ t'
u_disj : u.PairwiseDisjoint B
hu : ∀ a ∈ t', ∃ b ∈ u, (B a ∩ B b).Nonempty ∧ r a ≤ 2 * r b
ut : u ⊆ t
u_count : u.Countable
x : α
h : x ∈ s \ ⋃ a ∈ u, B a
v : Set ι := {a : ι | a ∈ u ∧ (B a ∩ ball x (R x)).Nonempty}
vu : v ⊆ u
K : ℝ
μK : LT.lt (α := ℝ≥0∞) ((μ : (a : Set α) → ℝ≥0∞) (closedBall x K) : ℝ≥0∞) (∞ : ℝ≥0∞)
hK : ∀ a ∈ u, (B a ∩ ball x (R x)).Nonempty → B a ⊆ closedBall x K
ε : ℝ≥0∞
εpos : 0 < ε
I : LT.lt (α := ℝ≥0∞) (∑' (a : (↑v : Type u_2)), (μ : (a : Set α) → ℝ≥0∞) (B (↑a : ι))) ∞
w : Finset (↑v : Type u_2)
hw :
  ∑' (a : { a : (↑v : Type u_2) // a ∉ w }), (μ : (a : Set α) → ℝ≥0∞) (B (↑(↑a : (↑v : Type u_2)) : ι)) <
    ε / (↑C : ℝ≥0∞)
z : α
hz : z ∈ (s \ ⋃ a ∈ u, B a) ∩ ball x (R x)
k : Set α := ⋃ a ∈ w, B (↑a : ι)
⊢ IsClosed[PseudoMetricSpace.toUniformSpace.toTopologicalSpace] k

Tactic:
have k_closed : IsClosed k := isClosed_biUnion_finset fun i _ => h't _ (ut (vu i.2))