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arXiv · 1909.04281

On parametrized families of numerical semigroups

Franklin Kerstetter·Christopher O'Neill
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Abstract

A numerical semigroup is an additive subsemigroup of the non-negative integers. In this paper, we consider parametrized families of numerical semigroups of the form $P_n = \langle f_1(n), \ldots, f_k(n) \rangle$ for polynomial functions $f_i$. We conjecture that for large $n$, the Betti numbers, Frobenius number, genus, and type of $P_n$ each coincide with a quasipolynomial. This conjecture has already been proven in general for Frobenius numbers, and for the remaining quantities in the special case when $P_n = \langle n, n + r_2, \ldots, n + r_k \rangle$. Our main result is to prove our conjecture in the case where each $f_i$ is linear. In the process, we develop the notion of weighted factorization length, and generalize several known results for standard factorization lengths and delta sets to this weighted setting.

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Franklin Kerstetter, Christopher O'Neill. 2019-09-10. On parametrized families of numerical semigroups. https://arxiv.org/abs/1909.04281

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