Star versions of Hurewicz spaces

Year 2021, Volume: 50 Issue: 5, 1325 - 1333, 15.10.2021

Sumit Singh , Ljubiša D. R. Kočinac

https://doi.org/10.15672/hujms.819719

Cited By: 7

Abstract

A space $X$ is said to have the set star Hurewicz property if for each nonempty subset $A$ of $X$ and each sequence $(\mathcal{U}_n: n\in \mathbb{N})$ of collections of sets open in $X$ such that for each $n\in \mathbb N$, $\overline{A} \subset \cup \mathcal{U}_n$, there is a sequence $(\mathcal{V}_n: n \in \mathbb{N})$ such that for each $n \in \mathbb{N}$, $\mathcal{V}_n$ is a finite subset of $\mathcal{U}_n$ and for each $x \in A$, $x \in {\rm St}(\cup\mathcal{V}_n, \mathcal{U}_n)$ for all but finitely many $n$. In this paper, we investigate the relationships among set star Hurewicz, set strongly star Hurewicz and other related covering properties and study the topological properties of these topological spaces.

Keywords

Hurewicz, star-Hurewicz, strongly star-Hurewicz, set star Hurewicz, set-SSH

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