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arXiv · 1302.0207

Many toric ideals generated by quadratic binomials possess no quadratic Gr\"obner bases

Takayuki Hibi·Kenta Nishiyama·Hidefumi Ohsugi·Akihiro Shikama
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Abstract

Let $G$ be a finite connected simple graph and $I_{G}$ the toric ideal of the edge ring $K[G]$ of $G$. In the present paper, we study finite graphs $G$ with the property that $I_{G}$ is generated by quadratic binomials and $I_{G}$ possesses no quadratic Gr\"obner basis. First, we give a nontrivial infinite series of finite graphs with the above property. Second, we implement a combinatorial characterization for $I_{G}$ to be generated by quadratic binomials and, by means of the computer search, we classify the finite graphs $G$ with the above property, up to 8 vertices.

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Takayuki Hibi, Kenta Nishiyama, Hidefumi Ohsugi, Akihiro Shikama. 2013-02-01. Many toric ideals generated by quadratic binomials possess no quadratic Gr\"obner bases. https://arxiv.org/abs/1302.0207

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