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Idempotent-generated semigroups and pseudovarieties

Part of: Semigroups

Published online by Cambridge University Press:  20 June 2011

J. Almeida
Affiliation:
Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal (jalmeida@fc.up.pt)
A. Moura
Affiliation:
Laboratório de Engenharia Matemática, Instituto Superior de Engenharia do Porto, Rua Dr António Bernardino de Almeida 431, 4200-072 Porto, Portugal and Centro de Matemática, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal (aim@isep.ipp.pt)
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Abstract

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The operator that constructs the pseudovariety generated by the idempotent-generated semi-groups of a given pseudovariety is investigated. Several relevant examples of pseudovarieties generated by their idempotent-generated elements are given, as well as some properties of this operator. Particular attention is paid to the pseudovarieties in {J, R, L, DA} concerning this operator and their generator ranks and idempotent-generator ranks.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 2011

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