English
Related papers

Related papers: Complete Solution for the Rainbow Numbers of Match…

200 papers

Given an edge-colored graph $G$, we denote the number of colors as $c(G)$, and the number of edges as $e(G)$. An edge-colored graph is rainbow if no two edges share the same color. A proper $mK_3$ is a vertex disjoint union of $m$ rainbow…

Combinatorics · Mathematics 2024-02-29 Jürgen Kritschgau , tahda queer , Cyrus Young , Wohua Zhou

A rainbow matching in an edge-colored graph is a matching in which no two edges have the same color. The color degree of a vertex v is the number of different colors on edges incident to v. Kritschgau [Electron. J. Combin. 27(2020)] studied…

Combinatorics · Mathematics 2021-05-25 Wenling Zhou

We prove that any family $E_1, \ldots , E_{\lceil rn \rceil}$ of (not necessarily distinct) sets of edges in an $r$-uniform hypergraph, each having a fractional matching of size $n$, has a rainbow fractional matching of size $n$ (that is, a…

Combinatorics · Mathematics 2020-01-27 Ron Aharoni , Ron Holzman , Zilin Jiang

Let $m,n,r,s$ be nonnegative integers such that $n\ge m=3r+s$ and $1\leq s\leq 3$. Let \[\delta(n,r,s)=\left\{\begin{array}{ll} n^2-(n-r)^2 &\text{if}\ s=1 , \\[5pt] n^2-(n-r+1)(n-r-1) &\text{if}\ s=2,\\[5pt] n^2 - (n-r)(n-r-1) &\text{if}\…

Combinatorics · Mathematics 2025-01-22 Hongliang Lu , Yan Wang

An exact r-coloring of a set $S$ is a surjective function $c:S \rightarrow \{1, 2, \ldots,r\}$. A rainbow solution to an equation over $S$ is a solution such that all components are a different color. We prove that every 3-coloring of…

Combinatorics · Mathematics 2023-05-25 Katie Ansaldi , Gabriel Cowley , Eric Green , Kihyun Kim , JT Rapp

The $k$-edge-colored bipartite Gallai-Ramsey number $\operatorname{bgr}_k(G:H)$ is defined as the minimum integer $n$ such that $n^2\geq k$ and for every $N\geq n$, every edge-coloring (using all $k$ colors) of complete bipartite graph…

Combinatorics · Mathematics 2023-12-15 Weizhen Chen , Meng Ji , Yaping Mao , Meiqin Wei

A path in a total-colored graph is called \emph{total rainbow} if its edges and internal vertices have distinct colors. For an $\ell$-connected graph $G$ and an integer $k$ with $1\leq k \leq\ell$, the \emph{total rainbow $k$-connection…

Combinatorics · Mathematics 2015-11-20 Wenjing Li , Xueliang Li , Di Wu

A subgraph of an edge-coloured complete graph is called rainbow if all its edges have different colours. In 1980 Hahn conjectured that every properly edge-coloured complete graph $K_n$ has a rainbow Hamiltonian path. Although this…

Combinatorics · Mathematics 2016-08-26 Noga Alon , Alexey Pokrovskiy , Benny Sudakov

The rainbow connection number, rc(G), of a connected graph G is the minimum number of colours needed to colour its edges, so that every pair of its vertices is connected by at least one path in which no two edges are coloured the same. In…

Combinatorics · Mathematics 2012-09-12 Manu Basavaraju , L. Sunil Chandran , Deepak Rajendraprasad , Arunselvan Ramaswamy

Given a graph $H$ and a positive integer $k$, the {\it $k$-colored Ramsey number} $R_k(H)$ is the minimum integer $n$ such that in every $k$-edge-coloring of the complete graph $K_{n}$, there is a monochromatic copy of $H$. Given two graphs…

Combinatorics · Mathematics 2025-11-07 Xihe Li , Xiangxiang Liu

A spanning tree of a properly edge-colored complete graph, $K_n$, is rainbow provided that each of its edges receives a distinct color. In 1996, Brualdi and Hollingsworth conjectured that if $K_{2m}$ is properly $(2m-1)$-edge-colored, then…

Combinatorics · Mathematics 2018-05-09 Hung-Lin Fu , Yuan-Hsun Lo , K. E. Perry , C. A. Rodger

Let $H$ be an edge colored hypergraph. We say that $H$ contains a \emph{rainbow} copy of a hypergraph $S$ if it contains an isomorphic copy of $S$ with all edges of distinct colors. We consider the following setting. A randomly edge colored…

Combinatorics · Mathematics 2015-06-10 Asaf Ferber , Michael Krivelevich

An exact $r$-coloring of a set $S$ is a surjective function $c:S\to [r]$. The rainbow number of a set $S$ for equation $eq$ is the smallest integer $r$ such that every exact $r$-coloring of $S$ contains a rainbow solution to $eq$. In this…

Combinatorics · Mathematics 2019-11-26 Katie Ansaldi , Houssein El Turkey , Jessica Hamm , Anisah Nu'Man , Nathan Warnberg , Michael Young

An edge-colored graph is called \textit{rainbow graph} if all the colors on its edges are distinct. Given a positive integer $n$ and a graph $G$, the \textit{anti-Ramsey number} $ar(n,G)$ is defined to be the minimum number of colors $r$…

Combinatorics · Mathematics 2025-06-10 Hongliang Lu , Xinyue Luo , Xinxin Ma

A well-studied coloring problem is to assign colors to the edges of a graph $G$ so that, for every pair of vertices, all edges of at least one shortest path between them receive different colors. The minimum number of colors necessary in…

Data Structures and Algorithms · Computer Science 2018-01-17 L. Sunil Chandran , Anita Das , Davis Issac , Erik Jan van Leeuwen

Rainbow connection number, $rc(G)$, of a connected graph $G$ is the minimum number of colours needed to colour its edges, so that every pair of vertices is connected by at least one path in which no two edges are coloured the same. In this…

Combinatorics · Mathematics 2011-05-31 L. Sunil Chandran , Rogers Mathew , Deepak Rajendraprasad

Given an edge-coloured graph, we say that a subgraph is rainbow if all of its edges have different colours. Let $\operatorname{ex}(n,H,$rainbow-$F)$ denote the maximal number of copies of $H$ that a properly edge-coloured graph on $n$…

Combinatorics · Mathematics 2022-02-28 Barnabás Janzer

Erdos and Sos proposed a problem of determining the maximum number F(n) of rainbow triangles in 3-edge-colored complete graphs on n vertices. They conjectured that F(n) = F(a)+ F(b)+F(c)+F(d)+abc+abd+acd+bcd, where a+b+c+d = n and a, b, c,…

Combinatorics · Mathematics 2018-06-04 Jozsef Balogh , Ping Hu , Bernard Lidicky , Florian Pfender , Jan Volec , Michael Young

An edge-colored graph $G$ is rainbow connected, if any two vertices are connected by a path whose edges have distinct colors. The rainbow connection number of a connected graph $G$, denoted $rc(G)$, is the smallest number of colors that are…

Combinatorics · Mathematics 2011-10-27 Xueliang Li , Mengmeng Liu , Ingo Schiermeyer

Consider the set $\{1,2,\dots,n\} = [n]$ and an equation $eq$. The rainbow number of $[n]$ for $eq$, denoted $\operatorname{rb}([n],eq)$, is the smallest number of colors such that for every exact $\operatorname{rb}([n], eq)$-coloring of…

Combinatorics · Mathematics 2020-06-09 Kean Fallon , Colin Giles , Hunter Rehm , Simon Wagner , Nathan Warnberg