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arXiv · 2007.11775

On powers of tight Hamilton cycles in randomly perturbed hypergraphs

Yulin Chang·Jie Han·Lubos Thoma
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Abstract

For integers $k \geq 3$ and $r\geq 2$, we show that for every $\alpha> 0$, there exists $\varepsilon > 0$ such that the union of $k$-uniform hypergraph on $n$ vertices with minimum codegree at least $\alpha n$ and a binomial random $k$-uniform hypergraph $G^{(k)}(n,p)$ with $p\geq n^{-{\binom{k+r-2}{k-1}}^{-1}-\varepsilon}$ on the same vertex set contains the $r^{th}$ power of a tight Hamilton cycle with high probability. Moreover, a construction shows that one cannot take $\varepsilon > C\alpha$, where $C=C(k,r)$ is a constant. Thus the bound on $p$ is optimal up to the value of $\varepsilon$ and this answers a question of Bedenknecht, Han, Kohayakawa, and Mota.

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Yulin Chang, Jie Han, Lubos Thoma. 2020-07-23. On powers of tight Hamilton cycles in randomly perturbed hypergraphs. https://arxiv.org/abs/2007.11775

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