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arXiv · 2012.13357

Genera of numerical semigroups and polynomial identities for degrees of syzygies

Leonid G. Fel
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Abstract

We derive polynomial identities of arbitrary degree $n$ for syzygies degrees of numerical semigroups S_m= and show that for n>=m they contain higher genera G_r=\sum_{s\in Z_>\setminus S_m}s^r of S_m. We find a number g_m=B_m-m+1 of algebraically independent genera G_r and equations, related any of g_m+1 genera, where B_m=\sum_{k=1}^{m-1}\beta_k and \beta_k denote the total and partial Betti numbers of non-symmetric semigroups. The number g_m is strongly dependent on symmetry of S_m and decreases for symmetric semigroups and complete intersections.

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Leonid G. Fel. 2020-12-24. Genera of numerical semigroups and polynomial identities for degrees of syzygies. https://arxiv.org/abs/2012.13357

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