Document Type : Original Manuscript

Authors

1 Department of Mathematics, Shahid Chamran University of Ahvaz, P.O. Box 6135783151, Ahvaz, Iran.

2 Department of Science, Petroleum University of Technology, P.O. Box 6318714317, Ahvaz, Iran.

Abstract

Let $C_c(X)$ (resp., $C_c^*(X)$) denote the functionally
countable subalgebra of $C(X)$ (resp., $C^*(X)$),
consisting of all functions (resp., bounded functions) with countable image.
$C_c(X)$ (resp., $C_c^*(X)$) as a topological ring via $m_c$-topology (resp., $m^*_c$-topology) and $u_c$-topology (resp., $u^*_c$-topology) is investigated and the equality of the latter two topologies is characterized.
Topological spaces which are called $N$-spaces are introduced and studied.
It is shown that the $m_c$-topology on $C_c(X)$ and its relative topology as a subspace of $C(X)$ (with $m$-topology) coincide if and only if $X$ is an $N$-space. We also show that $X$ is pseudocompact if and only if it is both a countably pseudocompact, and an $N$-space.

Keywords

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