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Cardinal invariants for C-cross topologies

Andrzej Kucharski·Szymon Plewik
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Abstract

C-cross topologies are introduced. Modifcations of the Kuratowski-Ulam Theorem are considered. Cardinal invariants add, cof, cov and non with respect to meager or nowhere dense subsets are compared. Remarks on invariants cof(nwdY) are mentioned for dense subspaces Y of X.

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Andrzej Kucharski, Szymon Plewik. 2006-09-13. Cardinal invariants for C-cross topologies. https://arxiv.org/abs/math/0609351

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