Mathlib Map

Theorems · Definition · general topology

IsCountablyCompact

{E : Type u_2} → [TopologicalSpace E] → Set E → Prop

A set A is countably compact if every countably generated proper filter f with f ≤ 𝓟 A has a cluster point in A.

Defined in
Mathlib.Topology.Compactness.CountablyCompact
Cited by
33 results in Mathlib
Foundations
Depth 49 from the axioms · uses propext, Quot.sound
Assumes
TopologicalSpace

Around this declaration

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

CountablyCompactSpace.isCountablyCompact_univ · cited by 3CountablyCompactSpace.isC…IsCountablyCompact.of_seq_clusterPt · cited by 3IsCountablyCompact.of_seq…isCountablyCompact_iff_seq_clusterPt · cited by 2isCountablyCompact_iff_se…IsCountablyCompact.elim_finite_subcover · cited by 2IsCountablyCompact.elim_f…IsLindelof.isCompact · cited by 2IsLindelof.isCompactisCountablyCompact_iff_countable_open_cover · cited by 1isCountablyCompact_iff_co…isCountablyCompact_iff_countable_open_cover' · cited by 1isCountablyCompact_iff_co…isCountablyCompact_iff_countablyCompactSpace · cited by 1isCountablyCompact_iff_co…isCountablyCompact_iff_isCountablyCompact_univ · cited by 1isCountablyCompact_iff_is…isCountablyCompact_univ_iff · cited by 1isCountablyCompact_univ_i…IsSeqCompact.isCountablyCompact · cited by 1IsSeqCompact.isCountablyC…Topology.IsEmbedding.isCountablyCompact_iff · cited by 1IsEmbedding.isCountablyCo…IsCountablyCompact.elim_directed_cover · cited by 1IsCountablyCompact.elim_d…IsCountablyCompact.exists_accPt_of_infinite · cited by 1IsCountablyCompact.exists…IsCountablyCompact.image · cited by 1IsCountablyCompact.imageSet · cited by 53352SetTopologicalSpace · cited by 24529TopologicalSpaceFilter · cited by 8121FilterFilter.NeBot · cited by 853Filter.NeBotFilter.principal · cited by 740Filter.principalFilter.IsCountablyGenerated · cited by 220Filter.IsCountablyGenerat…ClusterPt · cited by 138ClusterPtIsCountablyCompactCITED BYCITES

Cites7

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

Cited by35

Results whose statement or proof uses this declaration.