Abstract
The purpose of this paper is to study the notion of a ψ-porosity point and ψ-porosity topology, generated by it analogously to the porosity topology on the real line. The paper includes a necessary and sufficient conditions under which two ψ-porous topologies generated by two functions ψ1 and ψ2 are equal. The condition is formulated in terms of the behavior of two sequences of sets
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