Filter.Tendsto.countable_compl_preimage_ker

∀ {α : Type u_2} {β : Type u_3} {f : α → β} {l : Filter β} [l.IsCountablyGenerated],
  Filter.Tendsto f Filter.cofinite l → (f ⁻¹' l.ker)ᶜ.Countable

If f tends to a countably generated filter l along Filter.cofinite, then for all but countably many elements, f x ∈ l.ker.

Defined in: Mathlib.Order.Filter.Cofinite
Cited by: 2 results in Mathlib
Foundations: Depth 75 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes: Filter.IsCountablyGenerated

Around this declaration

Dashed lines are statement dependencies; solid lines are citations in proofs.

Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.

Results whose statement or proof uses this declaration.