On conditions for the Brandt semigroup to be non-isomorphic to the variant.
DOI:
https://doi.org/10.31558/1817-2237.2019.1-2.3Keywords:
Brandt semigroup, variant, sandwich semigroup, bicyclic semigroupAbstract
In this paper we study the question if the Brandt semigroup can be a variant of another semigroup or not. For a semigroup which does not contain a bicyclic subsemigroup we proved that a variant of such semigroup is not a Brandt semigroup. For an infinite semigroup which contains a bicyclic subsemigroup a variant with a sandwich element from this bicyclic subsemigroup is not a Brandt semigroup.
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