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arXiv · 2312.06013

Minimal free resolution of generalized repunit algebras

Isabel Colaço·Ignacio Ojeda
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Abstract

Let $\Bbbk$ be an arbitrary field and let $b > 1, n > 1$ and $a$ be three positive integers. In this paper we explicitly describe a minimal $S-$graded free resolution of the semigroup algebra $\Bbbk[S]$ when $S$ is a generalized repunit numerical semigroup, that is, when $S$ is the submonoid of $\mathbb{N}$ generated by $\{a_1, a_2, \ldots, a_n\}$ where $a_1 = \sum_{j=0}^{n-1} b^j$ and $a_i - a_{i-1} = a\, b^{i-2},\ i = 2, \ldots, n$, with $\gcd(a,a_1) = 1$.

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Isabel Colaço, Ignacio Ojeda. 2023-12-10. Minimal free resolution of generalized repunit algebras. https://doi.org/10.1080/00927872.2024.2394968

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