On Intersection and Co-maximal Hypergraph of $\mathbb{Z}_n$

Sachin Ballal; Ardra A N

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arXiv · 2509.14618

On Intersection and Co-maximal Hypergraph of $\mathbb{Z}_n$

Sachin Ballal·Ardra A N

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Abstract

The aim of this paper is to study the intersection hypergraph $\tilde{\Gamma}_\mathcal{H}(\mathbb{Z}_n)$ and co-maximal hypergraph $Co_\mathcal{H}(\mathbb{Z}_n)$ on the subgroups of $\mathbb{Z}_n$. We prove that the intersection and co-maximal hypergraph of a finite abelian group are isomorphic. Hence, we focus on $\tilde{\Gamma}_\mathcal{H}(\mathbb{Z}_n)$ and examine some of the structural properties, viz., diameter, girth and chromatic number of $\tilde{\Gamma}_\mathcal{H}(\mathbb{Z}_n)$. Also, we provide characterizations for hypertrees, star structures of $\tilde{\Gamma}_\mathcal{H}(\mathbb{Z}_n)$, and investigate the planarity and non-planarity of $\tilde{\Gamma}_\mathcal{H}(\mathbb{Z}_n)$.

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Sachin Ballal, Ardra A N. 2025-09-18. On Intersection and Co-maximal Hypergraph of $\mathbb{Z}_n$. https://arxiv.org/abs/2509.14618

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