Remarks on Star Countable Discrete Closed Spaces

نویسنده

  • Yan-Kui Song
چکیده

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 20 = 21 , there exists a normal absolutely star countable discrete closed space having a regular-closed subspace which is not star countable.

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تاریخ انتشار 2016