Abstract
In this paper the notions ofK-nets andK-bases are introduced and the corresponding cardinal functions,K-netweight andK-weight, are studied. Spaces with smallK-nets orK-bases are in some sense close to compact spaces. It turns out that the ordinary weight and net-weight can be easily expressed in terms of theK-versions and some auxiliary functions, moreover under some restrictions, weight and net-weight actually coincide with the hereditary modifications ofK-weight andK-netweight, respectively.
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Juhász, I. A generalization of nets and bases. Period Math Hung 7, 183–192 (1976). https://doi.org/10.1007/BF02082694
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DOI: https://doi.org/10.1007/BF02082694