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arXiv · 1812.03656

The cyclic index of adjacency tensor of generalized power hypergraphs

Yi-Zheng Fan·Min Li
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Abstract

Let $G$ be a $t$-uniform hypergraph, and let $c(G)$ denote the cyclic index of the adjacency tensor of $G$. Let $m,s,t$ be positive integers such that $t \ge 2$, $s \ge 2$ and $m=st$. The generalized power $G^{m,s}$ of $G$ is obtained from $G$ by blowing up each vertex into an $s$-set and preserving the adjacency relation. It was conjectured that $c(G^{m,s})=s \cdot c(G)$. In this paper we show that the conjecture is false by giving a counterexample, and give some sufficient conditions for the conjecture holding. Finally we give an equivalent characterization of the equality in the conjecture by using a matrix equation over $\mathbb{Z}_m$.

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Yi-Zheng Fan, Min Li. 2018-12-10. The cyclic index of adjacency tensor of generalized power hypergraphs. https://doi.org/10.1016/j.disc.2021.112329

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