p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
⊢ False
p q : ℚ
s t : Set ℚ
⊢ ¬IsCountablyGenerated (cocompact ℚ)
intro H
case intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hx : Tendsto x atTop (cocompact ℚ ⊓ 𝓝 0)
⊢ False
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
⊢ False
rcases exists_seq_tendsto (cocompact ℚ ⊓ 𝓝 0) with ⟨x, hx⟩
case intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hx : Tendsto x atTop (cocompact ℚ) ∧ Tendsto x atTop (𝓝 0)
⊢ False
case intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hx : Tendsto x atTop (cocompact ℚ ⊓ 𝓝 0)
⊢ False
rw [tendsto_inf] at hx
case intro.intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
⊢ False
case intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hx : Tendsto x atTop (cocompact ℚ) ∧ Tendsto x atTop (𝓝 0)
⊢ False
rcases hx with ⟨hxc, hx0⟩
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
⊢ ∃ n, ¬x n ∈ insert 0 (range x)

case intro.intro.intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
n : ℕ
hn : ¬x n ∈ insert 0 (range x)
⊢ False
case intro.intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
⊢ False
obtain ⟨n, hn⟩ : ∃ n : ℕ, x n ∉ insert (0 : ℚ) (range x)
case intro.intro.intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
n : ℕ
hn : ¬x n ∈ insert 0 (range x)
⊢ False
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
⊢ ∃ n, ¬x n ∈ insert 0 (range x)

case intro.intro.intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
n : ℕ
hn : ¬x n ∈ insert 0 (range x)
⊢ False
exact (hxc.eventually hx0.isCompact_insert_range.compl_mem_cocompact).exists
no goals
case intro.intro.intro
p q : ℚ
s t : Set ℚ
H : IsCountablyGenerated (cocompact ℚ)
x : ℕ → ℚ
hxc : Tendsto x atTop (cocompact ℚ)
hx0 : Tendsto x atTop (𝓝 0)
n : ℕ
hn : ¬x n ∈ insert 0 (range x)
⊢ False
exact hn (Or.inr ⟨n, rfl⟩)