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Related papers: Tight Hamilton cycles in random hypergraphs

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We study the appearance of powers of Hamilton cycles in pseudorandom graphs, using the following comparatively weak pseudorandomness notion. A graph $G$ is $(\varepsilon,p,k,\ell)$-pseudorandom if for all disjoint $X$ and $Y\subset V(G)$…

Combinatorics · Mathematics 2014-02-07 Peter Allen , Julia Böttcher , Hiep Hàn , Yury Person , Yoshiharu Kohayakawa

In this paper we consider the existence of Hamilton cycles in the random graph $G=G_{n,m}^{\delta\geq 3}$. This a random graph chosen uniformly from the set of graphs with vertex set $[n]$, $m$ edges and minimum degree at least 3. Our…

Combinatorics · Mathematics 2020-06-23 Michael Anastos , Alan Frieze

In 1963, Anton Kotzig famously conjectured that $K_{n}$, the complete graph of order $n$, where $n$ is even, can be decomposed into $n-1$ perfect matchings such that every pair of these matchings forms a Hamilton cycle. The problem is still…

Combinatorics · Mathematics 2025-10-03 Stefan Glock , Amedeo Sgueglia

A covering of a digraph $D$ by Hamilton cycles is a collection of directed Hamilton cycles (not necessarily edge-disjoint) that together cover all the edges of $D$. We prove that for $1/2 \geq p\geq \frac{\log^{20} n}{n}$, the random…

Combinatorics · Mathematics 2024-10-18 Asaf Ferber , Marcelo Sales , Mason Shurman

We use a randomised embedding method to prove that for all \alpha>0 any sufficiently large oriented graph G with minimum in-degree and out-degree \delta^+(G),\delta^-(G)\geq (3/8+\alpha)|G| contains every possible orientation of a Hamilton…

Combinatorics · Mathematics 2009-08-06 Luke Kelly

A famous result by R\"odl, Ruci\'nski, and Szemer\'edi guarantees a (tight) Hamilton cycle in $k$-uniform hypergraphs $H$ on $n$ vertices with minimum $(k-1)$-degree $\delta_{k-1}(H)\geq (1/2+o(1))n$, thereby extending Dirac's result from…

Combinatorics · Mathematics 2021-04-14 Felix Joos , Marcus Kühn , Bjarne Schülke

An $n$-vertex graph is called pancyclic if it contains a cycle of length $t$ for all $3 \leq t \leq n$. In this paper, we study pancyclicity of random graphs in the context of resilience, and prove that if $p \gg n^{-1/2}$, then the random…

Combinatorics · Mathematics 2015-03-17 Choongbum Lee , Wojciech Samotij

For a given graph $G$ of minimum degree at least $k$, let $G_p$ denote the random spanning subgraph of $G$ obtained by retaining each edge independently with probability $p=p(k)$. We prove that if $p \ge \frac{\log k + \log \log k +…

Combinatorics · Mathematics 2016-09-14 Roman Glebov , Humberto Naves , Benny Sudakov

We present a general method for counting and packing Hamilton cycles in dense graphs and oriented graphs, based on permanent estimates. We utilize this approach to prove several extremal results. In particular, we show that every nearly…

Combinatorics · Mathematics 2015-11-13 Asaf Ferber , Michael Krivelevich , Benny Sudakov

We show that provided $\log^{50} n/n \leq p \leq 1 - n^{-1/4}\log^9 n$ we can with high probability find a collection of $\lfloor \delta(G)/2 \rfloor$ edge-disjoint Hamilton cycles in $G \sim G_{n, p}$, plus an additional edge-disjoint…

Combinatorics · Mathematics 2013-05-09 Fiachra Knox , Daniela Kühn , Deryk Osthus

In this paper we prove a sufficient condition for the existence of a Hamilton cycle, which is applicable to a wide variety of graphs, including relatively sparse graphs. In contrast to previous criteria, ours is based on only two…

Combinatorics · Mathematics 2007-05-23 Dan Hefetz , Michael Krivelevich , Tibor Szabo

We study properties of random subcomplexes of partitions returned by (a suitable form of) the Strong Hypergraph Regularity Lemma, which we call regular slices. We argue that these subcomplexes capture many important structural properties of…

Combinatorics · Mathematics 2014-11-19 Peter Allen , Julia Böttcher , Oliver Cooley , Richard Mycroft

For $0\leq \ell <k$, a Hamiltonian $\ell$-cycle in a $k$-uniform hypergraph $H$ is a cyclic ordering of the vertices of $H$ in which the edges are segments of length $k$ and every two consecutive edges overlap in exactly $\ell$ vertices. We…

Combinatorics · Mathematics 2021-11-01 Asaf Ferber , Liam Hardiman , Adva Mond

Let $H$ be an edge colored hypergraph. We say that $H$ contains a \emph{rainbow} copy of a hypergraph $S$ if it contains an isomorphic copy of $S$ with all edges of distinct colors. We consider the following setting. A randomly edge colored…

Combinatorics · Mathematics 2015-06-10 Asaf Ferber , Michael Krivelevich

We show that w.h.p.\ the random $r$-uniform hypergraph $H_{n,m}$ contains a loose Hamilton cycle, provided $r\geq 3$ and $m\geq \frac{(1+\epsilon)n\log n}{r}$, where $\epsilon$ is an arbitrary positive constant. This is asymptotically best…

Combinatorics · Mathematics 2025-03-10 Alan Frieze , Xavier Perez-Gimenez

We show that with high probability we can build a Hamilton cycle after at most $1.85 n$ rounds in a particular semi-random model. In this model, in one round, we are given a {uniform random} $v\in[n]$ and then we can add an {arbitrary} edge…

Combinatorics · Mathematics 2022-08-16 Alan Frieze , Gregory B. Sorkin

We determine the sharp threshold for Hamilton cycles in randomly perturbed sparse graphs. For any $\alpha=\alpha(n)=o(1)$, let $G_{\alpha}$ be an $n$-vertex graph with minimum degree $\delta(G_{\alpha})\ge\alpha n$. We prove that if…

Combinatorics · Mathematics 2026-05-29 Guorui Ma , Zhifei Yan

A loose Hamilton cycle in a hypergraph is a cyclic sequence of edges covering all vertices in which only every two consecutive edges intersect and do so in exactly one vertex. With Dirac's theorem in mind, it is natural to ask what minimum…

Combinatorics · Mathematics 2024-04-29 Kalina Petrova , Miloš Trujić

For positive integers $r > \ell \geq 1$, an $\ell$-cycle in an $r$-uniform hypergraph is a cycle where each edge consists of $r$ vertices and each pair of consecutive edges intersect in $\ell$ vertices. For $\ell \geq 2$, we determine the…

Combinatorics · Mathematics 2025-01-08 Byron Chin

Compared to the classical binomial random (hyper)graph model, the study of random regular hypergraphs is made more challenging due to correlations between the occurrence of different edges. We develop an edge-switching technique for…

Combinatorics · Mathematics 2019-07-26 Alberto Espuny Díaz , Felix Joos , Daniela Kühn , Deryk Osthus