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weakly countably compact (Definition)

A topological space $X$ is said to be weakly countably compact (or limit point compact) if every infinite subset of $X$ has a limit point.

Every countably compact space is weakly countably compact. The converse is true in $\mathrm{T}_1$ spaces.

A metric space is weakly countably compact if and only if it is compact.

An easy example of a space $X$ that is not weakly countably compact is any infinite set with the discrete topology. A more interesting example is the countable complement topology on an uncountable set.




"weakly countably compact" is owned by yark. [ full author list (2) | owner history (2) ]
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See Also: compact, countably compact, sequentially compact, pseudocompact space

Other names:  limit point compact, limit-point compact
Also defines:  limit point compactness, weak countable compactness
Keywords:  topology
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Cross-references: uncountable set, countable complement topology, discrete topology, compact, metric space, converse, countably compact, limit point, infinite subset, topological space
There are 7 references to this entry.

This is version 5 of weakly countably compact, born on 2002-01-04, modified 2007-05-28.
Object id is 1234, canonical name is LimitPointCompact.
Accessed 8393 times total.

Classification:
AMS MSC54D30 (General topology :: Fairly general properties :: Compactness)

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