Natural Science, Mathematics, 2025
ON π-EXTENSIONS OF THE SEMIGROUP Z+
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Submitted: 2025-02-18; Published: 2025-02-18
© 2025 by author(s) and The Gufo Inc.
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Abstract
In the paper inverseπ-extensions of the semigroupZ+are studied. It is shownthatπ-extension of the semigroupZ+is inverse, if and only if itsπ-extension coincideswithπ(Z+). The existence of a non-inverseπ-extension for any abelian semigroup isproved.