Nonexistence of coreflections and coproducts in some subcategories of semigroups
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- by P. G. Trotter PDF
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Abstract:
It is shown here that there are no nontrivial free regular semigroups, free regular semigroups on a semigroup or free products of regular semigroups. Analogous results are obtained in the categories of simple, bisimple and bisimple regular semigroups.References
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Additional Information
- © Copyright 1980 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 80 (1980), 10-14
- MSC: Primary 18A30; Secondary 18A40, 18B99, 20M50
- DOI: https://doi.org/10.1090/S0002-9939-1980-0574500-5
- MathSciNet review: 574500