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arXiv · 2504.13311

Epimorphisms and pseudovarieties

Jorge Almeida·Aftab Hussain Shah
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Abstract

For each of the following conditions, we characterize the pseudovarieties of semigroups V that satisfy it: (i) every epimorphism to a member of V is onto; (ii) every epimorphism to a finite semigroup with domain a member of V is onto; (iii) for every epimorphism from S to T with S in V and T finite, T is also a member of V.

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Jorge Almeida, Aftab Hussain Shah. 2025-04-17. Epimorphisms and pseudovarieties. https://arxiv.org/abs/2504.13311

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