English
Related papers

Related papers: An update on the middle levels problem

200 papers

The semi-random graph process is an adaptive random graph process in which an online algorithm is initially presented an empty graph on $n$ vertices. In each round, a vertex $u$ is presented to the algorithm independently and uniformly at…

Combinatorics · Mathematics 2024-12-24 Alan Frieze , Pu Gao , Calum MacRury , Paweł Prałat , Gregory Sorkin

Chen, Faudree, Gould, Jacobson, and Lesniak determined the minimum degree threshold for which a balanced $k$-partite graph has a Hamiltonian cycle. We give an asymptotically tight minimum degree condition for Hamiltonian cycles in arbitrary…

Combinatorics · Mathematics 2019-10-10 Louis DeBiasio , Robert A. Krueger , Dan Pritikin , Eli Thompson

\noindent An \textit{\(m \times n\) grid graph} is the induced subgraph of the square lattice whose vertex set consists of all integer grid points \(\{(i,j) : 0 \leq i < m,\ 0 \leq j < n\}\). Let $H$ and $K$ be Hamiltonian cycles in an $m…

Combinatorics · Mathematics 2026-01-13 Albi Kazazi

The Hamiltonian cycle (HC) problem in graph theory is a well-known NP-complete problem. We present an approach in terms of $\mathbb{Z}_2$ lattice gauge theory (LGT) defined on the lattice with the graph as its dual. When the coupling…

Quantum Physics · Physics 2022-02-18 Xiaopeng Cui , Yu Shi

Given a graph on $n$ vertices and an assignment of colours to the edges, a rainbow Hamilton cycle is a cycle of length $n$ visiting each vertex once and with pairwise different colours on the edges. Similarly (for even $n$) a rainbow…

Combinatorics · Mathematics 2016-02-17 Deepak Bal , Patrick Bennett , Xavier Pérez-Giménez , Paweł Prałat

In a graph whose vertices are assigned integer ranks, a path is well-ranked if the endpoints have distinct ranks or some interior point has a higher rank than the endpoints. A ranking is an assignment of ranks such that all nontrivial paths…

Combinatorics · Mathematics 2016-07-26 Jordan Almeter , Samet Demircan , Andrew Kallmeyer , Kevin G. Milans , Robert Winslow

A Hamilton cycle in a directed graph $G$ is a cycle that passes through every vertex of $G$. A Hamiltonian decomposition of $G$ is a partition of its edge set into disjoint Hamilton cycles. In the late $60$s Kelly conjectured that every…

Combinatorics · Mathematics 2016-10-03 Asaf Ferber , Eoin Long , Benny Sudakov

The construction of the random intersection graph model is based on a random family of sets. Such structures, which are derived from intersections of sets, appear in a natural manner in many applications. In this article we study the…

Combinatorics · Mathematics 2023-06-22 Katarzyna Rybarczyk

In the random hypergraph $H_{n,p;k}$ each possible $k$-tuple appears independently with probability $p$. A loose Hamilton cycle is a cycle in which every pair of adjacent edges intersects in a single vertex. We prove that if $p n^{k-1}/\log…

Combinatorics · Mathematics 2011-02-24 Andrzej Dudek , Alan Frieze

The aim of this paper is to extend and generalise some work of Katona on the existence of perfect matchings or Hamilton cycles in graphs subject to certain constraints. The most general form of these constraints is that we are given a…

Combinatorics · Mathematics 2013-10-23 J. Robert Johnson

Wu in 1999 conjectured that if $H$ is a subgraph of the complete graph $K_{2n+1}$ with $n$ edges, then there is a Hamiltonian cycle decomposition of $K_{2n+1}$ such that each edge of $H$ is in a separate Hamiltonian cycle. The conjecture…

Combinatorics · Mathematics 2024-03-27 Ramin Javadi , Meysam Miralaei

We say that a $k$-uniform hypergraph $C$ is a Hamilton cycle of type $\ell$, for some $1\le \ell \le k$, if there exists a cyclic ordering of the vertices of $C$ such that every edge consists of $k$ consecutive vertices and for every pair…

Combinatorics · Mathematics 2011-02-09 Deepak Bal , Alan Frieze

Motivated to find the answers to some of the questions that have occurred in recent papers dealing with Hamiltonian cycles (abbreviated HCs) in some special classes of grid graphs we started the investigation of spanning unions of cycles,…

Combinatorics · Mathematics 2021-12-10 Jelena Djokić , Olga Bodroža-Pantić , Ksenija Doroslovački

We conjecture that every oriented graph $G$ on $n$ vertices with $\delta ^+ (G) , \delta ^- (G) \geq 5n/12$ contains the square of a Hamilton cycle. We also give a conjectural bound on the minimum semidegree which ensures a perfect packing…

Combinatorics · Mathematics 2010-11-22 Andrew Treglown

An \textit{\(m \times n\) grid graph} is the induced subgraph of the square lattice whose vertex set consists of all integer grid points \(\{(i,j) : 0 \leq i < m,\ 0 \leq j < n\}\). Let $H$ and $K$ be Hamiltonian cycles in an $m \times n$…

Combinatorics · Mathematics 2026-01-13 Albi Kazazi

In this paper, we develop a new rainbow Hamilton framework, which is of independent interest, settling the problem proposed by Gupta, Hamann, M\"{u}yesser, Parczyk, and Sgueglia when $k=3$, and draw the general conclusion for any $k\geq3$…

Combinatorics · Mathematics 2023-02-02 Yucong Tang , Bin Wang , Guanghui Wang , Guiying Yan

We investigate minimum vertex degree conditions for $3$-uniform hypergraphs which ensure the existence of loose Hamilton cycles. A loose Hamilton cycle is a spanning cycle in which only consecutive edges intersect and these intersections…

Combinatorics · Mathematics 2016-03-16 E. Buß , H. Hàn , M. Schacht

When solving the Hamiltonian path problem it seems natural to be given additional precedence constraints for the order in which the vertices are visited. For example one could decide whether a Hamiltonian path exists for a fixed starting…

Discrete Mathematics · Computer Science 2025-02-28 Jesse Beisegel , Fabienne Ratajczak , Robert Scheffler

We study the 2-offer semirandom 3-uniform hypergraph model on $n$ vertices. At each step, we are presented with 2 uniformly random vertices. We choose any other vertex, thus creating a hyperedge of size 3. We show a strategy that constructs…

Combinatorics · Mathematics 2024-09-26 Michael Molloy , Pawel Pralat , Gregory B. Sorkin

Building on the results of our previous work on Euclidean leaper tours, considering all integers $k>1$ and $h>0$, we study the existence of Hamiltonian cycles in the vertex set $C(2,k):=\{0,1\}^k$ of the $k$-dimensional hypercube when the…

Combinatorics · Mathematics 2026-03-24 Gabriele Di Pietro , Marco Ripà