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Isolated subsemigroups in the variants of T_n

Volodymyr Mazorchuk·Galyna Tsyaputa
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Abstract

We classify all isolated, completely isolated, and convex subsemigroups in the semigroup T_n of all transformations of an n-element set, considered as the semigroup with respect to a sandwich operation.

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Volodymyr Mazorchuk, Galyna Tsyaputa. 2007-08-30. Isolated subsemigroups in the variants of T_n. https://arxiv.org/abs/math/0503489

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