Vol. 12 (2006)
Articles

A note on \(\aleph_0\) - spaces

Yin Ge
Department of Mathematics, Suzhou University, Suzhou, P.R. China

Published 24-01-2025

Keywords

  • strong cs-network,
  • weakly hereditarily closure-preserving family,
  • sequential space,
  • \(\aleph_0\) - spaces

Abstract

In this paper, we prove that a space is an \(\aleph_0\)- space if it is an \(\aleph_1\)-compact space with a \(\sigma\)-weakly hereditarily closure-preserving strong \(cs\)-network. As an application of this result, we prove that a space with a nontrivial convergent sequence is an \(\aleph_0\)-space if it has a \(\sigma\)-weakly hereditarily closure-preserving strong \(cs\)-network.