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Related papers: Conflict-free hypergraph matchings

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A conflict-free k-coloring of a graph assigns one of k different colors to some of the vertices such that, for every vertex v, there is a color that is assigned to exactly one vertex among v and v's neighbors. Such colorings have…

A path in an(a) edge(vertex)-colored graph is called \emph{a conflict-free path} if there exists a color used on only one of its edges(vertices). An(A) edge(vertex)-colored graph is called \emph{conflict-free (vertex-)connected} if there is…

Combinatorics · Mathematics 2018-09-20 Meng Ji , Xueliang Li , Xiaoyu Zhu

A graph is "$H$-free" if it has no induced subgraph isomorphic to $H$. A conjecture of Conlon, Fox and Sudakov states that for every graph $H$, there exists $s>0$ such that in every $H$-free graph with $n>1$ vertices, either some vertex has…

Combinatorics · Mathematics 2020-12-08 Maria Chudnovsky , Jacob Fox , Alex Scott , Paul Seymour , Sophie Spirkl

The $k$-Strong Conflict-Free ($k$-SCF, in short) colouring problem seeks to find a colouring of the vertices of a hypergraph $H$ using minimum number of colours so that in every hyperedge $e$ of $H$, there are at least $\min\{|e|,k\}$…

Combinatorics · Mathematics 2021-06-08 S. M. Dhannya , N. S. Narayanaswamy

In this paper we study some variants of Dirac-type problems in hypergraphs. First, we show that for $k\ge 3$, if $H$ is a $k$-graph on $n\in k\mathbb N$ vertices with independence number at most $n/p$ and minimum codegree at least…

Combinatorics · Mathematics 2018-02-20 Jie Han

We develop a notion of containment for independent sets in hypergraphs. For every $r$-uniform hypergraph $G$, we find a relatively small collection $C$ of vertex subsets, such that every independent set of $G$ is contained within a member…

Combinatorics · Mathematics 2014-12-01 David Saxton , Andrew Thomason

A proper vertex colouring of a graph $G$ is referred to as conflict-free if in the neighbourhood of every vertex some colour appears exactly once, while it is called $h$-conflict-free if there are at least $h$ such colours for each vertex…

Combinatorics · Mathematics 2022-12-20 Mateusz Kamyczura , Jakub Przybyło

We describe and analyse a simple greedy algorithm \2G\ that finds a good 2-matching $M$ in the random graph $G=G_{n,cn}^{\d\geq 3}$ when $c\geq 15$. A 2-matching is a spanning subgraph of maximum degree two and $G$ is drawn uniformly from…

Combinatorics · Mathematics 2011-08-09 Alan Frieze

A conflict-free coloring of a graph $G$ is a (partial) coloring of its vertices such that every vertex $u$ has a neighbor whose assigned color is unique in the neighborhood of $u$. There are two variants of this coloring, one defined using…

Discrete Mathematics · Computer Science 2024-03-12 Sriram Bhyravarapu , Tim A. Hartmann , Hung P. Hoang , Subrahmanyam Kalyanasundaram , I. Vinod Reddy

Let $H$ be a $(k+1)$-uniform hypergraph which is nearly $D$-regular, such that any set of $i$ vertices is contained in at most $D_i$ edges of $H$ for each $i = 2, 3, \dots, k+1$. Influential results of Pippenger and of Frankl and R\"odl…

Combinatorics · Mathematics 2025-11-17 Stephen Gould , Tom Kelly

$ $We study the $d$-Uniform Hypergraph Matching ($d$-UHM) problem: given an $n$-vertex hypergraph $G$ where every hyperedge is of size $d$, find a maximum cardinality set of disjoint hyperedges. For $d\geq3$, the problem of finding the…

Data Structures and Algorithms · Computer Science 2020-09-22 Oussama Hanguir , Clifford Stein

We introduce and study conflict-free colourings of $t$-subsets in hypergraphs. In such colourings, one assigns colours to all subsets of vertices of cardinality $t$ such that in any hyperedge of cardinality at least $t$ there is a uniquely…

Combinatorics · Mathematics 2024-03-26 Bruno Jartoux , Chaya Keller , Shakhar Smorodinsky , Yelena Yuditsky

Let $F$ be a strictly $k$-balanced $k$-uniform hypergraph with $e(F)\geq |F|-k+1$ and maximum co-degree at least two. The random greedy $F$-free process constructs a maximal $F$-free hypergraph as follows. Consider a random ordering of the…

Combinatorics · Mathematics 2015-02-03 Daniela Kühn , Deryk Osthus , Amelia Taylor

Haxell's condition is a natural hypergraph analog of Hall's condition, which is a well-known necessary and sufficient condition for a bipartite graph to admit a perfect matching. That is, when Haxell's condition holds it forces the…

Data Structures and Algorithms · Computer Science 2016-12-06 Chidambaram Annamalai

A conflict-free $k$-coloring of a graph $G=(V,E)$ assigns one of $k$ different colors to some of the vertices such that, for every vertex $v$, there is a color that is assigned to exactly one vertex among $v$ and $v$'s neighbors. Such…

Computational Geometry · Computer Science 2017-09-13 Sándor P. Fekete , Phillip Keldenich

The H-free process, for some fixed graph H, is the random graph process defined by starting with an empty graph on n vertices and then adding edges one at a time, chosen uniformly at random subject to the constraint that no H subgraph is…

Combinatorics · Mathematics 2015-05-13 Tom Bohman , Peter Keevash

A proper conflict-free coloring of a graph is a proper vertex coloring wherein each non-isolated vertex's open neighborhood contains at least one color appearing exactly once. For a non-negative integer $k$, a graph $G$ is said to be proper…

Combinatorics · Mathematics 2025-12-30 Yuting Wang , Xin Zhang

A conflict-free cut $F$ on a simple connected graph $G = (V, E)$ is defined as a set of edges $F \subseteq E$ such that $G-F$ is disconnected, and no two edges in $F$ are conflicting. The notion of conflicting edges is represented using an…

Combinatorics · Mathematics 2026-05-13 Subrahmanyam Kalyanasundaram , Subodh Kumar

Dirac's theorem determines the sharp minimum degree threshold for graphs to contain perfect matchings and Hamiltonian cycles. There have been various attempts to generalize this theorem to hypergraphs with larger uniformity by considering…

Combinatorics · Mathematics 2025-03-27 Hyunwoo Lee

A proper $k$-colouring of a graph $G$ is called $h$-conflict-free if every vertex $v$ has at least $\min\, \{h, {\rm deg}(v)\}$ colours appearing exactly once in its neighbourhood. Let $\chi_{\rm pcf}^h(G)$ denote the minimum $k$ such that…

Combinatorics · Mathematics 2026-02-12 Quentin Chuet , Tianjiao Dai , Qiancheng Ouyang , François Pirot