On semigroup rings with decreasing Hilbert function
Commutative Algebra
2016-02-02 v1
Abstract
In this paper we study the Hilbert function HR of one-dimensional semigroup rings R = k[[S]]. For some classes of semigroups, by means of the notion of support of the elements in S, we give conditions on the generators of S in order to have decreasing HR. When the embedding dimension v and the multiplicity e verify v + 3 ? e ? v + 4, the decrease of HR gives explicit description of the Apery set of S. In particular for e = v+3, we classify the semigroups with e = 13 and HR decreasing, further we show that HR is non-decreasing if e < 12. Finally we deduce that HR is non-decreasing for every Gorenstein semigroup ring with e ? v + 4.
Cite
@article{arxiv.1602.00327,
title = {On semigroup rings with decreasing Hilbert function},
author = {Anna Oneto and Grazia Tamone},
journal= {arXiv preprint arXiv:1602.00327},
year = {2016}
}