l3lab/ntp-mathlib huggingface dataset:
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
⊢ Finset.card s ≤ 5 ^ finrank ℝ E

Next tactic:
set A := ⋃ c ∈ s, ball (c : E) δ with hA
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
⊢ Finset.card s ≤ 5 ^ finrank ℝ E

Next tactic:
have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
⊢ Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)

Next tactic:
rintro c hc d hd hcd
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
c : E
hc : c ∈ ↑s
d : E
hd : d ∈ ↑s
hcd : c ≠ d
⊢ (Disjoint on fun c => ball c δ) c d

Next tactic:
apply ball_disjoint_ball
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    

Proof state:
case h
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
c : E
hc : c ∈ ↑s
d : E
hd : d ∈ ↑s
hcd : c ≠ d
⊢ δ + δ ≤ dist c d

Next tactic:
rw [dist_eq_norm]
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    

Proof state:
case h
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
c : E
hc : c ∈ ↑s
d : E
hd : d ∈ ↑s
hcd : c ≠ d
⊢ δ + δ ≤ ‖c - d‖

Next tactic:
convert h c hc d hd hcd
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    

Proof state:
case h.e'_3
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
c : E
hc : c ∈ ↑s
d : E
hd : d ∈ ↑s
hcd : c ≠ d
⊢ δ + δ = 1

Next tactic:
norm_num
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
⊢ Finset.card s ≤ 5 ^ finrank ℝ E

Next tactic:
have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    apply ball_subset_ball'
    calc
      δ + dist x 0 ≤ δ + 2 := by rw [dist_zero_right]; exact add_le_add le_rfl (hs x hx)
      _ = 5 / 2 := by norm_num
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
⊢ A ⊆ ball 0 ρ

Next tactic:
refine' iUnion₂_subset fun x hx => _
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
x : E
hx : x ∈ s
⊢ ball x δ ⊆ ball 0 ρ

Next tactic:
apply ball_subset_ball'
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    apply ball_subset_ball'
    

Proof state:
case h
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
x : E
hx : x ∈ s
⊢ δ + dist x 0 ≤ ρ

Next tactic:
calc
      δ + dist x 0 ≤ δ + 2 := by rw [dist_zero_right]; exact add_le_add le_rfl (hs x hx)
      _ = 5 / 2 := by norm_num
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    apply ball_subset_ball'
    calc
      δ + dist x 0 ≤ δ + 2 := by 

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
x : E
hx : x ∈ s
⊢ δ + dist x 0 ≤ δ + 2

Next tactic:
rw [dist_zero_right]
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    apply ball_subset_ball'
    calc
      δ + dist x 0 ≤ δ + 2 := by rw [dist_zero_right]; 

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
x : E
hx : x ∈ s
⊢ δ + ‖x‖ ≤ δ + 2

Next tactic:
exact add_le_add le_rfl (hs x hx)
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    apply ball_subset_ball'
    calc
      δ + dist x 0 ≤ δ + 2 := by rw [dist_zero_right]; exact add_le_add le_rfl (hs x hx)
      _ = 5 / 2 := by 

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
x : E
hx : x ∈ s
⊢ δ + 2 = 5 / 2

Next tactic:
norm_num
/-- Any `1`-separated set in the ball of radius `2` has cardinality at most `5 ^ dim`. This is
useful to show that the supremum in the definition of `Besicovitch.multiplicity E` is
well behaved. -/
theorem card_le_of_separated (s : Finset E) (hs : ∀ c ∈ s, ‖c‖ ≤ 2)
    (h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖) : s.card ≤ 5 ^ finrank ℝ E := by
  /- We consider balls of radius `1/2` around the points in `s`. They are disjoint, and all
    contained in the ball of radius `5/2`. A volume argument gives `s.card * (1/2)^dim ≤ (5/2)^dim`,
    i.e., `s.card ≤ 5^dim`. -/
  borelize E
  let μ : Measure E := Measure.addHaar
  let δ : ℝ := (1 : ℝ) / 2
  let ρ : ℝ := (5 : ℝ) / 2
  have ρpos : 0 < ρ := by norm_num
  set A := ⋃ c ∈ s, ball (c : E) δ with hA
  have D : Set.Pairwise (s : Set E) (Disjoint on fun c => ball (c : E) δ) := by
    rintro c hc d hd hcd
    apply ball_disjoint_ball
    rw [dist_eq_norm]
    convert h c hc d hd hcd
    norm_num
  have A_subset : A ⊆ ball (0 : E) ρ := by
    refine' iUnion₂_subset fun x hx => _
    apply ball_subset_ball'
    calc
      δ + dist x 0 ≤ δ + 2 := by rw [dist_zero_right]; exact add_le_add le_rfl (hs x hx)
      _ = 5 / 2 := by norm_num
  

Proof state:
E : Type u_1
inst✝² : NormedAddCommGroup E
inst✝¹ : NormedSpace ℝ E
inst✝ : FiniteDimensional ℝ E
s : Finset E
hs : ∀ c ∈ s, ‖c‖ ≤ 2
h : ∀ c ∈ s, ∀ d ∈ s, c ≠ d → 1 ≤ ‖c - d‖
this✝¹ : MeasurableSpace E := borel E
this✝ : BorelSpace E
μ : Measure E := Measure.addHaar
δ : ℝ := 1 / 2
ρ : ℝ := 5 / 2
ρpos : 0 < ρ
A : Set E := ⋃ c ∈ s, ball c δ
hA : A = ⋃ c ∈ s, ball c δ
D : Set.Pairwise (↑s) (Disjoint on fun c => ball c δ)
A_subset : A ⊆ ball 0 ρ
⊢ Finset.card s ≤ 5 ^ finrank ℝ E

Next tactic:
have I :
    (s.card : ℝ≥0∞) * ENNReal.ofReal (δ ^ finrank ℝ E) * μ (ball 0 1) ≤
      ENNReal.ofReal (ρ ^ finrank ℝ E) * μ (ball 0 1) :=
    calc
      (s.card : ℝ≥0∞) * ENNReal.ofReal (δ ^ finrank ℝ E) * μ (ball 0 1) = μ A := by
        rw [hA, measure_biUnion_finset D fun c _ => measurableSet_ball]
        have I : 0 < δ := by norm_num
        simp only [div_pow, μ.addHaar_ball_of_pos _ I]
        simp only [one_div, one_pow, Finset.sum_const, nsmul_eq_mul, mul_assoc]
      _ ≤ μ (ball (0 : E) ρ) := (measure_mono A_subset)
      _ = ENNReal.ofReal (ρ ^ finrank ℝ E) * μ (ball 0 1) := by
        simp only [μ.addHaar_ball_of_pos _ ρpos]