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arXiv · 2206.03704

Quasi-forest simplicial complexes and almost Cohen-Macaulay

Chwas Ahmed·Amir Mafi·Mohammed Rafiq Namiq
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Abstract

In this paper we study the quasi-forest simplicial complexes and we define the concept of simplicial $k$-cycle (denoted by $\mathcal{S}_k$) and simplicial $k$-point (denoted by $\mathcal{P}_k$). We show that a simplicial complex $Δ$ is quasi-forest if and only if it does not have any $\mathcal{P}_k$ and any $\mathcal{S}_k$ for $k\geq 3$. Furthermore we characterize almost Cohen-Macaulay quasi-forest simplicial complexes. In the end we show that the cycle graph $G=C_n$ is almost Cohen-Macaulay if and only if $n=3,4,5,6,7,8,9,11$.

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Chwas Ahmed, Amir Mafi, Mohammed Rafiq Namiq. 2022-06-08. Quasi-forest simplicial complexes and almost Cohen-Macaulay. https://arxiv.org/abs/2206.03704

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