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arXiv · 2607.00838

On the Linearity of Squarefree Powers of Edge Ideals

Francesco Navarra·Ayesha Asloob Qureshi·Naoki Terai
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Abstract

Let $G$ be a graph and $I(G)$ its edge ideal. The $p$-th squarefree power $I(G)^{[p]}$ is the monomial ideal generated by squarefree monomials corresponding to the matchings of size $p$ of $G$. In this paper, we provide a combinatorial characterization of when $I(G)^{[p]}$ is linearly related, i.e., when its first syzygy module is generated by linear forms. Moreover, for a $1$-dimensional flag simplicial complex $\Delta$ and its Stanley-Reisner ideal $I_{\Delta}$, which arises as the edge ideal of the complement graph of $\Delta$, we describe the shape of the Betti table of $I_{\Delta}^{[p]}$ and we give a combinatorial characterization of when $I_{\Delta}^{[p]}$ has a linear resolution.

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Francesco Navarra, Ayesha Asloob Qureshi, Naoki Terai. 2026-07-01. On the Linearity of Squarefree Powers of Edge Ideals. https://arxiv.org/abs/2607.00838

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