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arXiv · 1512.00345

The short resolution of a semigroup algebra

Ignacio Ojeda·Alberto Vigneron-Tenorio
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Abstract

This work generalizes the short resolution given in Proc. Amer. Math. Soc. \textbf{131}, 4, (2003), 1081--1091, to any affine semigroup. Moreover, a characterization of Ap\'{e}ry sets is given. This characterization lets compute Ap\'{e}ry sets of affine semigroups and the Frobenius number of a numerical semigroup in a simple way. We also exhibit a new characterization of the Cohen-Macaulay property for simplicial affine semigroups.

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Ignacio Ojeda, Alberto Vigneron-Tenorio. 2015-12-01. The short resolution of a semigroup algebra. https://arxiv.org/abs/1512.00345

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