A Lower Bound For Depths of Powers of Edge Ideals

Louiza Fouli; Susan Morey

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arXiv · 1409.7020

A Lower Bound For Depths of Powers of Edge Ideals

Louiza Fouli·Susan Morey

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Abstract

Let $G$ be a graph and let $I$ be the edge ideal of $G$. Our main results in this article provide lower bounds for the depth of the first three powers of $I$ in terms of the diameter of $G$. More precisely, we show that $\depth R/I^t \geq \left\lceil{\frac{d-4t+5}{3}} \right\rceil +p-1$, where $d$ is the diameter of $G$, $p$ is the number of connected components of $G$ and $1 \leq t \leq 3$. For general powers of edge ideals we show

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Louiza Fouli, Susan Morey. 2014-09-24. A Lower Bound For Depths of Powers of Edge Ideals. https://arxiv.org/abs/1409.7020

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