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Strongly σ-Metrizable Spaces Are Super σ-Metrizable
Banakh Iryna 1 , Banakh Taras Onufriyovych 2
1 Department of theory of functions and functional analysis, Ivan Franko National University of Lviv, Lviv, 79000, Ukraine
2 Department of Algebra, Topology and Fundamentals of Mathematics, Ivan Franko National University of Lviv, Lviv, 79000, Ukraine
Keywords: σ-Metrizable Spaces
Abstract

A topological space X is called strongly σ-metrizable if X=U_{n\in ω} X_n for an increasing sequence (X_n)_{n \in ω} of closed metrizable subspaces such that every convergence sequence in X is contained in some X_n. If, in addition, every compact subset of X is contained in some X_n, n \in ω, then X is called super σ-metrizable. Answering a question of V.K. Maslyuchenko and O.I. Filipchuk, we prove that a topological space is strongly σ-metrizable if and only if it is super σ-metrizable.

References

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Cite
ACS Style
Banakh, I.; Banakh, T.O. Strongly σ-Metrizable Spaces Are Super σ-Metrizable. Bukovinian Mathematical Journal. 2017, 5
AMA Style
Banakh I, Banakh TO. Strongly σ-Metrizable Spaces Are Super σ-Metrizable. Bukovinian Mathematical Journal. 2017; 5(1-2).
Chicago/Turabian Style
Iryna Banakh, Taras Onufriyovych Banakh. 2017. "Strongly σ-Metrizable Spaces Are Super σ-Metrizable". Bukovinian Mathematical Journal. 5 no. 1-2.
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