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arXiv · 1211.3693

The numerical duplication of a numerical semigroup

Marco D'Anna·Francesco Strazzanti
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Abstract

In this paper we present and study the numerical duplication of a numerical semigroup, a construction that, starting with a numerical semigroup $S$ and a semigroup ideal $E\subseteq S$, produces a new numerical semigroup, denoted by $S\Join^b\E$ (where $b$ is any odd integer belonging to $S$), such that $S=(S\Join^b\E)/2$. In particular, we characterize the ideals $E$ such that $S\Join^bE$ is almost symmetric and we determine its type.

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Marco D'Anna, Francesco Strazzanti. 2012-11-15. The numerical duplication of a numerical semigroup. https://arxiv.org/abs/1211.3693

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