Gaps in Nonsymmetric Numerical Semigroups

Leonid G. Fel; Francesca Aicardi

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arXiv · math/0703735

Gaps in Nonsymmetric Numerical Semigroups

Leonid G. Fel·Francesca Aicardi

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Abstract

There exist two different sorts of gaps in the nonsymmetric numerical additive semigroups finitely generated by a minimal set of positive integers {d_1,...,d_m}. The h-gaps are specific only for the nonsymmetric semigroups while the g-gaps are possessed by both, symmetric and nonsymmetric semigroups. We derive the generating functions for the corresponding sets of gaps, Delta_H({\bf d}^m) and Delta_G({\bf d}^m), and prove several statements on the minimal and maximal values of the h-gaps. Detailed description of both sorts of gaps is given for three special kinds of nonsymmetric semigroups: semigroups with maximal embedding dimension, semigroups of maximal and almost maximal length, and pseudo--symmetric semigroups.

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Leonid G. Fel, Francesca Aicardi. 2007-03-25. Gaps in Nonsymmetric Numerical Semigroups. https://arxiv.org/abs/math/0703735

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