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Related papers: Hamilton Cycles in Dense Regular Digraphs and Orie…

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Every graph of size $q$ (the number of edges) and minimum degree $\delta$ is hamiltonian if $q\le\delta^2+\delta-1$. The result is sharp.

Combinatorics · Mathematics 2011-07-13 Zh. G. Nikoghosyan

We prove that a random graph $G(n,p)$, with $p$ above the Hamiltonicity threshold, is typically such that for any $r$-colouring of its edges there exists a Hamilton cycle with at least $(2/(r+ 1)-o(1))n$ edges of the same colour. This…

Combinatorics · Mathematics 2021-04-22 Lior Gishboliner , Michael Krivelevich , Peleg Michaeli

The Nash-Williams conjecture establishes degree sequence conditions ensuring Hamilton cycles in digraphs. An asymptotic version of this conjecture for large digraphs was independently derived by several researchers. We strengthen these…

Combinatorics · Mathematics 2026-05-01 Zhilan Wang , Jin Yan

In light of Lov\'{a}sz's longstanding question on the existence of Hamilton paths in vertex-transitive graphs, this paper considers a natural variant: what if vertex-transitivity is relaxed, yet a high degree of symmetry--specifically…

Combinatorics · Mathematics 2026-02-17 Shaofei Du , Kai Yuan

We enumerate certain geometric equivalence classes of subgraphs induced by Hamiltonian paths and cycles in complete graphs. Said classes are orbits under the action of certain direct products of dihedral and cyclic groups on sets of strings…

Combinatorics · Mathematics 2021-08-31 Samuel Herman , Eirini Poimenidou

Let $D$ be a strongly connected directed graph of order $n\geq 4$ vertices which satisfies the following condition for every triple $x,y,z$ of vertices such that $x$ and $y$ are non-adjacent: If there is no arc from $x$ to $z$, then…

Combinatorics · Mathematics 2014-05-02 Samvel Kh. Darbinyan

For $1\le \ell<k/2$, we show that for sufficiently large $n$, every $k$-uniform hypergraph on $n$ vertices with minimum codegree at least $\frac n{2 (k-\ell)} $ contains a Hamilton $\ell$-cycle. This codegree condition is best possible and…

Combinatorics · Mathematics 2015-01-29 Jie Han , Yi Zhao

This paper presents sufficient conditions for Hamiltonian paths and cycles in graphs. Letting $\lambda\left( G\right) $ denote the spectral radius of the adjacency matrix of a graph $G,$ the main results of the paper are: (1) Let $k\geq1,$…

Combinatorics · Mathematics 2016-11-08 Vladimir Nikiforov

We prove a conjecture of Penrose about the standard random geometric graph process, in which n vertices are placed at random on the unit square and edges are sequentially added in increasing order of lengths taken in the l_p norm. We show…

Combinatorics · Mathematics 2009-07-28 Xavier Pérez-Giménez , Nicholas C. Wormald

We prove that for $r\in \mathbb{N}$ with $r\geq 2$ and $\mu>0$, there exist $\alpha>0$ and $n_{0}$ such that for every $n\geq n_{0}$, every $n$-vertex graph $G$ with $\delta(G)\geq \left(1-\frac{1}{r}+\mu\right)n$ and $\alpha(G)\leq \alpha…

Combinatorics · Mathematics 2023-05-30 Ming Chen , Jie Han , Yantao Tang , Donglei Yang

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 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 consider a robust variant of Dirac-type problems in $k$-uniform hypergraphs. For instance, we prove that if $H$ is a $k$-uniform hypergraph with minimum codegree at least $(1/2 + \gamma )n$, $\gamma >0$, and $n$ is sufficiently large,…

Combinatorics · Mathematics 2020-07-01 Sylwia Antoniuk , Nina Kamčev , Andrzej Ruciński

Let D be the circulant digraph with n vertices and connection set {2,3,c}. (Assume D is loopless and has outdegree 3.) Work of S.C.Locke and D.Witte implies that if n is a multiple of 6, c is either (n/2) + 2 or (n/2) + 3, and c is even,…

Combinatorics · Mathematics 2007-05-23 Dave Witte Morris , Joy Morris , Kerri Webb

Y. Manoussakis (J. Graph Theory 16, 1992, 51-59) proposed the following conjecture. \noindent\textbf{Conjecture}. {\it Let $D$ be a 2-strongly connected digraph of order $n$ such that for all distinct pairs of non-adjacent vertices $x$, $y$…

Combinatorics · Mathematics 2023-06-22 Samvel Kh. Darbinyan

After long term efforts, it was recently proved in \cite{DKM2} that except for the Peterson graph, every connected vertex-transitive graph of order $rs$ has a Hamilton cycle, where $r$ and $s$ are primes. A natural topic is to solve the…

Combinatorics · Mathematics 2022-03-28 Shaofei Du , Yao Tian , Hao Yu

In this paper, we study discrepancy questions for spanning subgraphs of $k$-uniform hypergraphs. Our main result is that, for any integers $k \ge 3$ and $r \ge 2$, any $r$-colouring of the edges of a $k$-uniform $n$-vertex hypergraph $G$…

Combinatorics · Mathematics 2025-07-02 Lior Gishboliner , Stefan Glock , Amedeo Sgueglia

For a graph $G$ the random $n$-lift of $G$ is obtained by replacing each of its vertices by a set of $n$ vertices, and joining a pair of sets by a random matching whenever the corresponding vertices of $G$ are adjacent. We show that…

Combinatorics · Mathematics 2014-01-07 Tomasz Łuczak , Łukasz Witkowski , Marcin Witkowski

We show that every $(n,d,\lambda)$-graph contains a Hamilton cycle for sufficiently large $n$, assuming that $d\geq \log^{6}n$ and $\lambda\leq cd$, where $c=\frac{1}{70000}$. This significantly improves a recent result of Glock, Correia…

Combinatorics · Mathematics 2025-07-02 Asaf Ferber , Jie Han , Dingjia Mao , Roman Vershynin

We prove that random hypergraphs are asymptotically almost surely resiliently Hamiltonian. Specifically, for any $\gamma>0$ and $k\ge3$, we show that asymptotically almost surely, every subgraph of the binomial random $k$-uniform hypergraph…

Combinatorics · Mathematics 2021-05-11 Peter Allen , Olaf Parczyk , Vincent Pfenninger