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arXiv · 2003.02558

HS-stability and complex products in involution semigroups

Bertalan Bodor·Erkko Lehtonen·Thomas Quinn-Gregson·Nikolaas Verhulst
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Abstract

When does the complex product of a given number of subsets of a group generate the same subgroup as their union? We answer this question in a more general form by introducing HS-stability and characterising the HS-stable involution subsemigroup generated by a subset of a given involution semigroup. We study HS-stability for the special cases of regular ${}^{*}$-semigroups and commutative involution semigroups.

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Bertalan Bodor, Erkko Lehtonen, Thomas Quinn-Gregson, Nikolaas Verhulst. 2020-03-05. HS-stability and complex products in involution semigroups. https://doi.org/10.1007/s00233-021-10213-x

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