compact space

(redirected from Countably compact)

compact space

[¦käm‚pakt ′spās]
(mathematics)
A topological space which is a compact set.
References in periodicals archive ?
A subset A of X is called I-sequentially countably compact if any infinite subset A has at least one I-sequentially accumulation point in A.
A subset of X is I-sequentially compact if and only if it is I-sequentially countably compact.
Next suppose A is any I-sequentially countably compact subset of X.
A subset of X is I-sequentially compact if and only if it is sequentially countably compact in the ordinary sense.
ii) strongly countably compact if every countable cover of X by preopen sets has a finite subcover and countably S-closed [resp:countably P-closed] if every countable cover of X by regular closed [resp: preclosed] sets has a finite subcover.
iii) mildly compact (mildly countably compact, mildly Lindelof) if every clopen cover (respectively, clopen countable cover, clopen cover) of X has a finite (respectively, a finite, a countable) subcover.
mildly countably compact, mildly Lindelof), then Y is nearly compact (resp.