Abstract
A semigroup S has a midunit u if aub=ab for all a and b in S. It is the purpose of this paper to explore semigroups containing midunits and to find an analog to the group of units. The concepts of rectangular group and Bruck-Reilly construction will be extended to produce some semigroups with midunits, and an abstract characterization will be made of certain of these semigroups.
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Communicated by P. A. Grillet
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Ault, J.E. Semigroups with midunits. Semigroup Forum 6, 346–351 (1973). https://doi.org/10.1007/BF02389143
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DOI: https://doi.org/10.1007/BF02389143