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arXiv · 1906.05510

Binomial edge ideals of cographs

Thomas Kahle·Jonas Krüsemann
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Abstract

We determine the Castelnuovo-Mumford regularity of binomial edge ideals of complement reducible graphs (cographs). For cographs with $n$ vertices the maximum regularity grows as $2n/3$. We also bound the regularity by graph theoretic invariants and construct a family of counterexamples to a conjecture of Hibi and Matsuda.

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Thomas Kahle, Jonas Krüsemann. 2021-03-10. Binomial edge ideals of cographs. https://arxiv.org/abs/1906.05510

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