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arXiv · 2009.02312

Symbolic Powers of Cover Ideals of Graphs and Koszul Property

Yan Gu·Huy Tài Hà·Joseph W. Skelton
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Abstract

We show that attaching a whisker (or a pendant) at the vertices of a cycle cover of a graph results in a new graph with the following property: all symbolic powers of its cover ideal are Koszul or, equivalently, componentwise linear. This extends previous work where the whiskers were added to all vertices or to the vertices of a vertex cover of the graph.

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Yan Gu, Huy Tài Hà, Joseph W. Skelton. 2020-09-04. Symbolic Powers of Cover Ideals of Graphs and Koszul Property. https://doi.org/10.1142/s0218196721500405

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