The Join of the Pseudovariety J with Permutative Pseudovarieties

  • Assis de Azevedo


Using a theorem of Reiterman, which characterizes pseudovarieties as classes of finite semigroups satisfying a set of pseudoidentities, and a characterization of the implict operations on DS, we calculate some joins of the form JV, where V is a permutative pseudovariety. As a consequence we obtain that, for these V, JV is decidable if and only if VCS is decidable.


Semi Group Topological Semigroup Hasse Diagram Finite Semigroup Implicit Operation 
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Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • Assis de Azevedo
    • 1
  1. 1.Centro de MatemáticaUniversidade do MinhoBragaPortugal

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