Countable Complement Space is Not Weakly Countably Compact
From ProofWiki
Theorem
Let $T = \left({S, \tau}\right)$ be a countable complement topology on an uncountable set $S$.
Then $T$ is not weakly countably compact.
Proof
From Limit Points of Countable Complement Space, if $H \subseteq S$ is countable, it contains all its limit points.
Sources
- Lynn Arthur Steen and J. Arthur Seebach, Jr.: Counterexamples in Topology (1970)... (previous)... (next): $\text{II}: \ 20: \ 7$