Documentation

Mathlib.Order.Filter.AtTopBot.Finset

Filter.atTop and Filter.atBot filters and finite sets. #

theorem Filter.atTop_finset_eq_iInf {α : Type u_3} :
atTop = ⨅ (x : α), principal (Set.Ici {x})
theorem Filter.tendsto_atTop_finset_of_monotone {α : Type u_3} {β : Type u_4} [Preorder β] {f : βFinset α} (h : Monotone f) (h' : ∀ (x : α), ∃ (n : β), x f n) :

If f is a monotone sequence of Finsets and each x belongs to one of f n, then Tendsto f atTop atTop.

theorem Monotone.tendsto_atTop_finset {α : Type u_3} {β : Type u_4} [Preorder β] {f : βFinset α} (h : Monotone f) (h' : ∀ (x : α), ∃ (n : β), x f n) :

Alias of Filter.tendsto_atTop_finset_of_monotone.


If f is a monotone sequence of Finsets and each x belongs to one of f n, then Tendsto f atTop atTop.

theorem Filter.tendsto_finset_image_atTop_atTop {β : Type u_4} {γ : Type u_5} [DecidableEq β] {i : βγ} {j : γβ} (h : Function.LeftInverse j i) :
theorem Filter.tendsto_finset_preimage_atTop_atTop {α : Type u_3} {β : Type u_4} {f : αβ} (hf : Function.Injective f) :
Tendsto (fun (s : Finset β) => s.preimage f ) atTop atTop
theorem Filter.eventually_finset_atTop_subset {α : Type u_3} (i : Finset α) :
∀ᶠ (s : Finset α) in atTop, i s

Every finset is eventually a subset of s along atTop.

theorem Filter.eventually_finset_mem_atTop {α : Type u_3} (i : α) :
∀ᶠ (s : Finset α) in atTop, i s

Every element of α is eventually a member of s along atTop on Finset α.

The pushforward of atTop on Finset α along Finset.card is atTop on , when α is infinite.

The pushforward of atTop on Finset α along Finset.card is pure (Fintype.card α), when α is finite.

Finset.card tends to atTop along atTop on Finset α, when α is infinite.

Finset.card tends to pure (Fintype.card α), when α is finite.

theorem Filter.tendsto_comp_card_atTop_iff {α : Type u_3} {β : Type u_4} [Infinite α] {f : β} {l : Filter β} :
Tendsto (fun (s : Finset α) => f s.card) atTop l Tendsto f atTop l

Tendsto along atTop for a function precomposed with Finset.card reduces to Tendsto along atTop on , when α is infinite.

theorem Filter.tendsto_comp_card_atTop_iff_of_fintype {α : Type u_3} {β : Type u_4} [Fintype α] {f : β} {l : Filter β} :
Tendsto (fun (s : Finset α) => f s.card) atTop l Tendsto f (pure (Fintype.card α)) l

Tendsto along atTop for a function precomposed with Finset.card reduces to Tendsto along pure (Fintype.card α), when α is finite.