Theorems · Theorem · general topology
IsCountablyCompact.of_isClosed_subset
∀ {E : Type u_2} [inst : TopologicalSpace E] {A B : Set E},
IsCountablyCompact A → IsClosed B → B ⊆ A → IsCountablyCompact BA closed subset of a countably compact set is countably compact.
- Cited by
- 1 results in Mathlib
- Foundations
- Depth 76 from the axioms · uses propext, Classical.choice, Quot.sound
- Assumes
- TopologicalSpace
Around this declaration
Dashed lines are statement dependencies; solid lines are citations in proofs.
Cites13
Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.
- Setstatement and proof · cited by 53,352
- TopologicalSpacestatement and proof · cited by 24,529
- Filterproof · cited by 8,121
- LE.le.transproof · cited by 3,151
- IsClosedstatement and proof · cited by 1,639
- Filter.NeBotproof · cited by 853
- Filter.principalproof · cited by 740
- Filter.IsCountablyGeneratedproof · cited by 220
- ClusterPtproof · cited by 138
- IsCountablyCompactstatement and proof · cited by 33
- Filter.principal_monoproof · cited by 30
- ClusterPt.monoproof · cited by 30
Cited by1
Results whose statement or proof uses this declaration.
- IsClosed.isCountablyCompactproof · cited by 0