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arXiv · 2302.00080

Rainbow Hamilton cycle in hypergraph system

Abstract

In this paper, we develop a new rainbow Hamilton framework, which is of independent interest, settling the problem proposed by Gupta, Hamann, Müyesser, Parczyk, and Sgueglia when $k=3$, and draw the general conclusion for any $k\geq3$ as follows. A $k$-graph system $\textbf{H}=\{H_i\}_{i\in[n]}$ is a family of not necessarily distinct $k$-graphs on the same $n$-vertex set $V$, moreover, a $k$-graph $H$ on $V$ is rainbow if $E(H)\subseteq \bigcup_{i\in[n]}E(H_i)$ and $|E(H)\cap E(H_i)|\leq1$ for $i\in[n]$. We show that given $γ> 0$, sufficiently large $n$ and an $n$-vertex $k$-graph system $\textbf{H}=\{H_i\}_{i\in[n]}$ , if $δ_{k-2}(H_i)\geq(5/9+γ)\binom{n}{2}$ for $i\in[n]$ where $k\geq3$, then there exists a rainbow tight Hamilton cycle. This result implies the conclusion in a single graph, which was proved by Lang and Sanhueza-Matamala [$J. Lond. Math. Soc., 2022$], Polcyn, Reiher, Rödl and Schülke [$J. Combin. Theory \ Ser. B, 2021$] independently.

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BibTeXRIS

Yucong Tang, Bin Wang, Guanghui Wang, Guiying Yan. 2023-01-31. Rainbow Hamilton cycle in hypergraph system. https://arxiv.org/abs/2302.00080

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