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arXiv · 2411.05251

Cochordal zero divisor graphs and Betti numbers of their edge ideals

Le Xuan Dung·Thanh Vu
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Abstract

We associate a sequence of positive integers, termed the type sequence, with a cochordal graph. Using this type sequence, we compute all graded Betti numbers of its edge ideal. We then classify all positive integer $n$ such that the zero divisor graph of $\mathbb{Z}/n \mathbb{Z}$ is cochordal and determine all the graded Betti numbers of its edge ideal.

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Le Xuan Dung, Thanh Vu. 2024-11-08. Cochordal zero divisor graphs and Betti numbers of their edge ideals. https://arxiv.org/abs/2411.05251

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