Abstract
The class semigroup of a numerical semigroup \(S\) is the semigroup \(\mathcal {S}(S)\) of classes of the relative ideals of \(S\). Our aim is to find some properties of \(\mathcal {S}(S)\). In particular we observe that \(\mathcal {S}(S)\) is finite and compute its cardinality in some cases, using the poset of gaps of \(S\). Moreover, we study the generators of \(\mathcal {S}(S)\) and the reduction number of its elements.
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We would like to thank the referee for her/his careful reading and helpful suggestions.
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Communicated by Fernando Torres.
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Barucci, V., Khouja, F. On the class semigroup of a numerical semigroup. Semigroup Forum 92, 377–392 (2016). https://doi.org/10.1007/s00233-014-9679-8
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DOI: https://doi.org/10.1007/s00233-014-9679-8