Relative size of subsets of a semigroup

2015/05/30 by Igor Protasov, Protasov, Igor, Serhii Slobodianiuk +1
Mathematics · #05D10 #20M12 #22A15 #FOS: Mathematics #General Topology (math.GN) #math.GN #msc:05D10 #msc:20M12 #msc:22A15

paper · pdf · doi:10.48550/arxiv.1506.00112

arxiv created 2015/05/30 · arxiv updated 2015/06/02

Abstract

Given a semigroup S, we introduce relative (with respect to a filter τ on S) versions of large, thick and prethick subsets of S, give the ultrafilter characterizations of these subsets and explain how large could be some cell in a finite partition of a subset A∈τ.

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