Math 2.0

General topology Compactness Concept

Countably compact space

Summary

A countably compact space is a topological space in which every countable open cover has a finite subcover. It is a weakening of compactness that is equivalent to the statement that every sequence has a cluster point. Compact spaces and sequentially compact spaces are countably compact. For metric spaces, countable compactness, compactness and sequential compactness all coincide.

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Further reading

  1. Web https://en.wikipedia.org/wiki/Countably_compact_space
About this page
TagS3N3CHZV89
URIm2://S3N3CHZV89
Kindconcept
WritingW0 stub
MSC54D30
SpecializesLimit point compact space
Same as
Changed2 November 2026

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