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Keywords:
pseudocompact; normal; Tychonoff; star countable; absolutely star countable; star countable discrete closed; absolutely star countable discrete closed space
pseudocompact; normal; Tychonoff; star countable; absolutely star countable; star countable discrete closed; absolutely star countable discrete closed space
Summary:
In this paper, we prove the following statements: (1) There exists a Tychonoff star countable discrete closed, pseudocompact space having a regular-closed subspace which is not star countable. (2) Every separable space can be embedded into an absolutely star countable discrete closed space as a closed subspace. (3) Assuming $2^{\aleph _0}=2^{\aleph _1}$, there exists a normal absolutely star countable discrete closed space having a regular-closed subspace which is not star countable.
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