English
The filter coclosedLindelof is generated by complements of closed Lindelöf sets.
Русский
Фильтр coclosedLindelof порождён дополнениями к замкнутым Линдельоф-множествам.
LaTeX
$$$\mathrm{coclosedLindelof}(X) = \bigwedge_{t:\text{Set }X,\ IsClosed(t),\ IsLindelof(t)} \mathcal{P}(t^c)$$$
Lean4
/-- `Filter.coclosedLindelof` is the filter generated by complements to closed Lindelof sets. -/
def coclosedLindelof (X : Type*) [TopologicalSpace X] : Filter X :=
-- `Filter.coclosedLindelof` is the filter generated by complements to closed Lindelof sets.
⨅ (s : Set X) (_ : IsClosed s) (_ : IsLindelof s), 𝓟 sᶜ