##  [Countable Compactness](/index.php/countable-compactness) 

  ##  [Countable Compactness](https://puremath.quantumdictionary.io/countable-compactness-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A topological property: a space is countably compact if every countable open cover has a finite subcover; equivalently (under the usual separation hypotheses) every countably infinite subset has an accumulation point.