Abstract
We show that a variety V of completely regular semigroups that contains a nontrivial (two-element) semilattice has finitary or unitary unification type if and only if V consists of strong semilattices of rectangular groups of finitary or unitary unification type. We reduce the problem of recognizing unification type of a variety V of completely regular semigroups defined by a homotypical system of identities to the same problem for the variety of all groups of V.
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Mashevitzky, G. Unification Types of Completely Regular Semigroups. Journal of Automated Reasoning 29, 171–182 (2002). https://doi.org/10.1023/A:1021695118634
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DOI: https://doi.org/10.1023/A:1021695118634