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arXiv · 1506.00112

Relative size of subsets of a semigroup

Igor Protasov·Serhii Slobodianiuk
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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 $A\inτ$.

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Igor Protasov, Serhii Slobodianiuk. 2015-05-30. Relative size of subsets of a semigroup. https://arxiv.org/abs/1506.00112

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