Regular Gδ-diagonals and some upper bounds for cardinality of topological spaces
نویسندگان
چکیده
We recall that for a Urysohn space X the regular diagonal degree ∆(X) of X is defined as the minimal infinite cardinal κ such that X has a regular 2010 Mathematics Subject Classification: Primary 54A25; Secondary 54D10, 54D20
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تاریخ انتشار 2015