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arXiv · 1906.01585

A geometrical characterization of proportionally modular affine semigroups

J. D. Díaz-Ramírez·J. I. García-García·A. Sánchez-R. -Navarro·A. Vigneron-Tenorio
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Abstract

A proportionally modular affine semigroup is the set of nonnegative integer solutions of a modular Diophantine inequality $f_1x_1+\cdots +f_nx_n \mod b \le g_1x_1+\cdots +g_nx_n$ where $g_1,\dots,g_n,$ $f_1,\ldots ,f_n\in \mathbb{Z}$ and $b\in\mathbb{N}$. In this work, a geometrical characterization of these semigroups is given. Moreover, some algorithms to check if a semigroup $S$ in $\mathbb{N}^n$, with $\mathbb{N}^n\setminus S$ a finite set, is a proportionally modular affine semigroup are provided by means of that geometrical approach.

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J. D. Díaz-Ramírez, J. I. García-García, A. Sánchez-R. -Navarro, A. Vigneron-Tenorio. 2019-06-04. A geometrical characterization of proportionally modular affine semigroups. https://arxiv.org/abs/1906.01585

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