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arXiv · 2607.02424

Symmetric edge polytopes are not gamma-positive

Luis Ferroni
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Abstract

A conjecture posed by Ohsugi and Tsuchiya (2019) postulates that the Ehrhart $h^*$-polynomials of symmetric edge polytopes are $γ$-positive. We disprove this conjecture by exhibiting an infinite family of counterexamples. The smallest example provided by our construction is a $36$-dimensional symmetric edge polytope.

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Luis Ferroni. 2026-07-02. Symmetric edge polytopes are not gamma-positive. https://arxiv.org/abs/2607.02424

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