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arXiv · 1705.06426

Regularity of powers of cover ideals of unimodular hypergraphs

Nguyen Thu Hang·Tran Nam Trung
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Abstract

Let $\H$ be a unimodular hypergraph over the vertex set $[n]$ and let $J(\H)$ be the cover ideal of $\H$ in the polynomial ring $R=K[x_1,\ldots,x_n]$. We show that $\reg J(\H)^s$ is a linear function in $s$ for all $s\geqslant r\left\lceil \frac{n}{2}\right\rceil+1$ where $r$ is the rank of $\H$. Moreover for every $i$, $a_i(R/J(\H)^s)$ is also a linear function in $s$ for $s \geqslant n^2$.

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Nguyen Thu Hang, Tran Nam Trung. 2017-05-18. Regularity of powers of cover ideals of unimodular hypergraphs. https://arxiv.org/abs/1705.06426

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