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Related papers: On Hamilton Decompositions

200 papers

In 1972, Woodall raised the following Ore type condition for directed Hamilton cycles in digraphs: Let $D$ be a digraph. If for every vertex pair $u$ and $v$, where there is no arc from $u$ to $v$, we have $d^+u)+d^-(v)\geq |D|$, then $D$…

Combinatorics · Mathematics 2017-10-20 Zan-Bo Zhang , Xiaoyan Zhang , Xuelian Wen

Thomassen conjectured that there is a function $f(k)$ such that every strongly $f(k)$-connected tournament contains $k$ edge-disjoint Hamiltonian cycles. This conjecture was recently proved by K\"uhn, Lapinskas, Osthus, and Patel who showed…

Combinatorics · Mathematics 2014-07-01 Alexey Pokrovskiy

Gishboliner, Krivelevich, and Michaeli (2023) conjectured the following generalization of Dirac's theorem: If the minimum degree $\delta$ of an $n$-vertex oriented graph $G$ is greater or equal to $n/2$, then $G$ has a Hamilton oriented…

Combinatorics · Mathematics 2026-02-12 Q. Guo , G. Gutin , Y. Lan , Q. Shao , A. Yeo , Y. Zhou

In this paper we prove the following results (via a unified approach) for all sufficiently large $n$: (i) [$1$-factorization conjecture] Suppose that $n$ is even and $D\geq 2\lceil n/4\rceil -1$. Then every $D$-regular graph $G$ on $n$…

Combinatorics · Mathematics 2014-10-23 Béla Csaba , Daniela Kühn , Allan Lo , Deryk Osthus , Andrew Treglown

The Hamilton-Waterloo problem asks for a decomposition of the complete graph into $r$ copies of a 2-factor $F_{1}$ and $s$ copies of a 2-factor $F_{2}$ such that $r+s=\left\lfloor\frac{v-1}{2}\right\rfloor$. If $F_{1}$ consists of…

Combinatorics · Mathematics 2017-12-27 Melissa Keranen , Adrián Pastine

For an orientation $H$ with $n$ vertices, let $T(H)$ denote the maximum possible number of labeled copies of $H$ in an $n$-vertex tournament. It is easily seen that $T(H) \ge n!/2^{e(H)}$ as the latter is the expected number of such copies…

Combinatorics · Mathematics 2015-11-25 Raphael Yuster

We study the existence of directed Hamilton cycles in random digraphs with $m$ edges where we condition on minimum in- and out-degree $\d \ge k+1$, where $k \ge 1$. Denote such a random graph by $D_{n,m}^{(\delta\geq k+1)}$. Let $m=cn$ and…

Combinatorics · Mathematics 2026-04-14 Colin Cooper , Alan Frieze

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

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

In this paper, we prove that for each $d \geq 2$, the union of a $d$-regular graph with a uniformly random $2$-factor on the same vertex set is Hamiltonian with high probability. This resolves a conjecture by Dragani\'c and Keevash for all…

Combinatorics · Mathematics 2025-08-26 Cicely , Henderson , Sean Longbrake , Dingjia Mao , Patryk Morawski

This MSci thesis surveys results in extremal graph theory, in particular relating to Hamilton cycles. Szem\'eredi's Regularity Lemma plays a central role. We also investigate the robust outexpansion property for digraphs. Kelly showed that…

Combinatorics · Mathematics 2014-06-30 Amelia Taylor

For a prime number p, we construct a generating set for the ring of invariants for the p+1 dimensional indecomposable modular representation of a cyclic group of order p^2. We then use the constructed invariants to describe the…

Commutative Algebra · Mathematics 2007-06-13 R. J. Shank , D. L. Wehlau

Rosenfeld Conjectured in 1972 that there exists an integer K $\geq$ 8 such that any tournament of order n $\geq$ K contains any Hamiltonian oriented path. In 2000, Havet and Thomass\'e proved this conjecture for any tournament with exactly…

Combinatorics · Mathematics 2020-12-01 Charbel Bou Hanna

We develop a theory of integrable dispersive deformations of 2+1 dimensional Hamiltonian systems of hydrodynamic type following the scheme proposed by Dubrovin and his collaborators in 1+1 dimensions. Our results show that the…

Exactly Solvable and Integrable Systems · Physics 2015-05-30 E. V. Ferapontov , V. S. Novikov , N. M. Stoilov

The \textit{acyclic disconnection} $\overrightarrow{\omega }(D)$ (resp. the \textit{directed triangle free disconnection } $\overrightarrow{\omega }_{3}(D)$) of a digraph $D$ is defined as the maximum possible number of connected components…

Combinatorics · Mathematics 2015-07-15 Bernardo Llano

We consider the problem of decomposing the edges of a digraph into as few paths as possible. A natural lower bound for the number of paths in any path decomposition of a digraph $D$ is $\frac{1}{2}\sum_{v\in V(D)}|d^+(v)-d^-(v)|$; any…

Combinatorics · Mathematics 2026-02-04 Viresh Patel , Mehmet Akif Yıldız

In Graph Theory a number of results were devoted to studying the computational complexity of the number modulo 2 of a graph's edge set decompositions of various kinds, first of all including its Hamiltonian decompositions, as well as the…

Discrete Mathematics · Computer Science 2010-05-14 Greg Cohen

We prove that for all countable tournaments $D$ the recently discovered compactification $|D|$ by their ends and limit edges contains a topological Hamilton path: a topological arc that contains every vertex. If $D$ is strongly connected,…

Combinatorics · Mathematics 2021-01-14 Ruben Melcher

In 1981, Bermond and Thomassen conjectured that for any positive integer $k$, every digraph with minimum out-degree at least $2k-1$ admits $k$ vertex-disjoint directed cycles. In this short paper, we verify the Bermond-Thomassen conjecture…

Combinatorics · Mathematics 2023-11-23 Gregory Gutin , Wei Li , Shujing Wang , Anders Yeo , Yacong Zhou

Motivated by the wide-ranging applications of Hamiltonian decompositions in distributed computing, coded caching, routing, resource allocation, load balancing, and fault tolerance, our work presents a comprehensive design for Hamiltonian…

Information Theory · Computer Science 2025-04-28 Javad Maheri , Petros Elia