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arXiv · 1907.07955

Irreducible Generalized Numerical Semigroups and uniqueness of the Frobenius element

Carmelo Cisto·Gioia Failla·Chris Peterson·Rosanna Utano
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Abstract

Let $\mathbb{N}^{d}$ be the $d$-dimensional monoid of non-negative integers. A generalized numerical semigroup is a submonoid $ S\subseteq \mathbb{N}^d$ such that $H(S)=\mathbb{N}^d \setminus S$ is a finite set. We introduce irreducible generalized numerical semigroups and characterize them in terms of the cardinality of a special subset of $H(S)$. In particular, we describe relaxed monomial orders on $\mathbb N^d$, define the Frobenius element of $S$ with respect to a given relaxed monomial order, and show that the Frobenius element of $S$ is independent of the order if the generalized numerical semigroup is irreducible.

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Carmelo Cisto, Gioia Failla, Chris Peterson, Rosanna Utano. 2019-07-18. Irreducible Generalized Numerical Semigroups and uniqueness of the Frobenius element. https://doi.org/10.1007/s00233-019-10040-1

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