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Related papers: Randomly colouring simple hypergraphs

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A classic result of Erd\H{o}s, Gy\'arf\'as and Pyber states that for every coloring of the edges of $K_n$ with $r$ colors, there is a cover of its vertex set by at most $f(r) = O(r^2 \log r)$ vertex-disjoint monochromatic cycles. In…

Combinatorics · Mathematics 2018-07-18 Dániel Korándi , Frank Mousset , Rajko Nenadov , Nemanja Škorić , Benny Sudakov

The problem of uniformly sampling hypergraph independent sets is revisited. We design an efficient perfect sampler for the problem under a condition similar to that of the asymmetric Lov\'asz Local Lemma. When applied to $d$-regular…

Data Structures and Algorithms · Computer Science 2022-09-14 Guoliang Qiu , Yanheng Wang , Chihao Zhang

Consider any dense r-regular quasirandom bipartite graph H with parts of size n and fix a set of r colours. Let L be a random list assignment where each colour is available for each edge of H with probability p. We show that the threshold…

Combinatorics · Mathematics 2022-12-09 Peter Keevash

Let a_1,...,a_k satisfy a_1+...+a_k=1 and suppose a k-uniform hypergraph on n vertices satisfies the following property; in any partition of its vertices into k sets A_1,...,A_k of sizes a_1*n,...,a_k*n, the number of edges intersecting…

Combinatorics · Mathematics 2010-02-02 Asaf Shapira , Raphael Yuster

The $\Delta$-vertex coloring problem has become one of the prototypical problems for understanding the complexity of local distributed graph problems on constant-degree graphs. The major open problem is whether the problem can be solved…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-04-08 Manuel Jakob , Yannic Maus

The study of graph vertex colorability from an algebraic perspective has introduced novel techniques and algorithms into the field. For instance, it is known that $k$-colorability of a graph $G$ is equivalent to the condition $1 \in…

Combinatorics · Mathematics 2007-09-24 Christopher J. Hillar , Troels Windfeldt

In the $\ell$-Coloring Problem, we are given a graph on $n$ nodes, and tasked with determining if its vertices can be properly colored using $\ell$ colors. In this paper we study below-guarantee graph coloring, which tests whether an…

Data Structures and Algorithms · Computer Science 2025-09-17 Shyan Akmal , Tomohiro Koana

A linearly ordered (LO) $k$-colouring of an $r$-uniform hypergraph assigns an integer from $\{1, \ldots, k \}$ to every vertex so that, in every edge, the (multi)set of colours has a unique maximum. Equivalently, for $r=3$, if two vertices…

Computational Complexity · Computer Science 2023-02-03 Tamio-Vesa Nakajima , Stanislav Živný

For fixed positive integers $r, k$ and $\ell$ with $1 \leq \ell < r$ and an $r$-uniform hypergraph $H$, let $\kappa (H, k,\ell)$ denote the number of $k$-colorings of the set of hyperedges of $H$ for which any two hyperedges in the same…

Combinatorics · Mathematics 2011-03-01 Carlos Hoppen , Yoshiharu Kohayakawa , Hanno Lefmann

We show that for any fixed integer $m \geq 1$, a graph of maximum degree $\Delta$ has a coloring with $O(\Delta^{(m+1)/m})$ colors in which every connected bicolored subgraph contains at most $m$ edges. This result unifies previously known…

Combinatorics · Mathematics 2022-09-28 Peter Bradshaw

We present an improved coupling technique for analyzing the mixing time of Markov chains. Using our technique, we simplify and extend previous results for sampling colorings and independent sets. Our approach uses properties of the…

Probability · Mathematics 2007-05-23 Thomas P. Hayes , Eric Vigoda

Graph coloring is one of the central problems in distributed graph algorithms. Much of the research on this topic has focused on coloring with $\Delta+1$ colors, where $\Delta$ denotes the maximum degree. Using $\Delta+1$ colors may be…

Data Structures and Algorithms · Computer Science 2017-08-24 Mohsen Ghaffari , Christiana Lymouri

We prove that the vertices of every $(r + 1)$-uniform hypergraph with maximum degree $\Delta$ may be coloured with $c(\frac{\Delta}{d + 1})^{1/r}$ colours such that each vertex is in at most $d$ monochromatic edges. This result, which is…

Combinatorics · Mathematics 2022-08-17 António Girão , Freddie Illingworth , Alex Scott , David R. Wood

An $r$-uniform hypergraph is uniquely $k$-colorable if there exists exactly one partition of its vertex set into $k$ parts such that every edge contains at most one vertex from each part. For integers $k \ge r \ge 2$, let $\Phi_{k,r}$…

Combinatorics · Mathematics 2024-09-04 Xizhi Liu , Jie Ma , Tianhen Wang , Tianming Zhu

We analyse the performance of simple distributed colouring algorithms under the assumption that the input graph is a hyperbolic random graph (HRG), a generative model capturing key properties of real-world networks such as power-law degree…

Data Structures and Algorithms · Computer Science 2025-07-23 Yannic Maus , Janosch Ruff

In this paper, perfect k-orthogonal colourings of tensor graphs are studied. First, the problem of determining if a given graph has a perfect 2-orthogonal colouring is reformulated as a tensor subgraph problem. Then, it is shown that if two…

Combinatorics · Mathematics 2022-01-11 Kyle MacKeigan

In this work we present a simple and efficient algorithm which, with high probability, provides an almost uniform sample from the set of proper k-colourings on an instance of a sparse random graph G(n,d/n), where k=k(d) is a sufficiently…

Discrete Mathematics · Computer Science 2008-06-26 Charilaos Efthymiou , Paul G. Spirakis

The $k$-colouring reconfiguration problem asks whether, for a given graph $G$, two proper $k$-colourings $\alpha$ and $\beta$ of $G$, and a positive integer $\ell$, there exists a sequence of at most $\ell+1$ proper $k$-colourings of $G$…

Computational Complexity · Computer Science 2014-10-30 Matthew Johnson , Dieter Kratsch , Stefan Kratsch , Viresh Patel , Daniël Paulusma

We extend the notion of spectral independence (introduced by Anari, Liu, and Oveis Gharan [ALO20]) from the Boolean domain to general discrete domains. This property characterises distributions with limited correlations, and implies that…

Data Structures and Algorithms · Computer Science 2020-07-17 Weiming Feng , Heng Guo , Yitong Yin , Chihao Zhang

We consider the problem of coloring a 3-colorable graph in polynomial time using as few colors as possible. This is one of the most challenging problems in graph algorithms. In this paper using Blum's notion of ``progress'', we develop a…

Data Structures and Algorithms · Computer Science 2024-06-04 Ken-ichi Kawarabayashi , Mikkel Thorup , Hirotaka Yoneda