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arXiv · 1112.3721

Ideals generated by diagonal 2-minors

Viviana Ene·Ayesha Asloob Qureshi
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Abstract

With a simple graph $G$ on $[n]$, we associate a binomial ideal $P_G$ generated by diagonal minors of an $n \times n$ matrix $X=(x_{ij})$ of variables. We show that for any graph $G$, $P_G$ is a prime complete intersection ideal and determine the divisor class group of $K[X]/ P_G$. By using these ideals, one may find a normal domain with free divisor class group of any given rank.

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Viviana Ene, Ayesha Asloob Qureshi. 2012-01-26. Ideals generated by diagonal 2-minors. https://arxiv.org/abs/1112.3721

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