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BY-NC-ND 3.0 license Open Access Published by De Gruyter Open Access June 28, 2013

On weaker forms of the chain (F) condition and metacompactness-like covering properties in the product spaces

  • Süleyman Önal EMAIL logo and Çetin Vural
From the journal Open Mathematics

Abstract

We introduce the concept of a family of sets generating another family. Then we prove that if X is a topological space and X has W = {W(x): x ∈ X} which is finitely generated by a countable family satisfying (F) which consists of families each Noetherian of ω-rank, then X is metaLindelöf as well as a countable product of them. We also prove that if W satisfies ω-rank (F) and, for every x ∈ X, W(x) is of the form W 0(x) ∪ W 1(x), where W 0(x) is Noetherian and W 1(x) consists of neighbourhoods of x, then X is metacompact.

MSC: 54D20; 03E02

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Published Online: 2013-6-28
Published in Print: 2013-9-1

© 2013 Versita Warsaw

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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