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arXiv · 2304.13690

Counting Ideals in Numerical Semigroups

Parth Chavan
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Abstract

If $S$ is a numerical semigroup, let $m(S,k)$ denote the number of ideals of $S$ with codimension $k$ and let $n(S,k)$ denote the number of ideals of $S$ with conductor $k$. We compute the generating function of the sequence $m(S,k)$ for all numerical semigroups of embedding dimension $2$ and for $S = \langle 3,n+2,2n+1\rangle$. We also prove that the sequence $n(S,k)$ becomes stationary after a certain term and compute the stationary terms for numerical semigroups of the form $\langle a,a+1 \rangle$.

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Parth Chavan. 2023-04-26. Counting Ideals in Numerical Semigroups. https://arxiv.org/abs/2304.13690

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