Cardinal invariants for C-cross topologies
نویسندگان
چکیده
C-cross topologies are introduced. Modifications 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 ⊆ X.
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