English
Related papers

Related papers: Rainbow and Gallai-Rado numbers involving binary f…

200 papers

The Gallai-Ramsey number $gr_{k}(K_{3}: H_{1}, H_{2}, \cdots, H_{k})$ is the smallest integer $n$ such that every $k$-edge-colored $K_{n}$ contains either a rainbow $K_3$ or a monochromatic $H_{i}$ in color $i$ for some $i\in [k]$. We find…

Combinatorics · Mathematics 2021-03-03 Xueli Su , Yan Liu

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

Given a linear equation $\mathcal{E}$, the $k$-color Rado number $R_k(\mathcal{E})$ is the smallest integer $n$ such that every $k$-coloring of $\{1,2,3,\dots,n\}$ contains a monochromatic solution to $\mathcal E$. The degree of regularity…

Combinatorics · Mathematics 2022-10-10 Yuan Chang , Jesús A. De Loera , William J. Wesley

In this paper we consider properly edge-colored graphs, i.e. two edges with the same color cannot share an endpoint, so each color class is a matching. A matching is called \it rainbow \rm if its edges have different colors. The minimum…

Combinatorics · Mathematics 2012-08-29 Andras Gyarfas , Gabor N. Sarkozy

A path in an edge (vertex)-colored graph $G$, where adjacent edges (vertices) may have the same color, is called a rainbow path if no pair of edges (internal vertices) of the path are colored the same. The rainbow (vertex) connection number…

Combinatorics · Mathematics 2011-05-24 Hengzhe Li , Xueliang Li , Yuefang Sun

There exists a minimum integer $N$ such that any 2-coloring of $\{1,2,...,N\}$ admits a monochromatic solution to $x+y+kz =\ell w$ for $k,\ell \in \mathbb{Z}^+$, where $N$ depends on $k$ and $\ell$. We determine $N$ when $\ell-k \in…

Combinatorics · Mathematics 2007-07-02 Aaron Robertson , Kellen Myers

The canonical Ramsey theorem of Erd\H{o}s and Rado implies that for any graph $H$, any edge-coloring (with an arbitrary number of colors) of a sufficiently large complete graph $K_N$ contains a monochromatic, lexicographic, or rainbow copy…

Combinatorics · Mathematics 2024-10-14 Lior Gishboliner , Aleksa Milojević , Benny Sudakov , Yuval Wigderson

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

Given a graph $G$ and a positive integer $k$, the \emph{Gallai-Ramsey number} is defined to be the minimum number of vertices $n$ such that any $k$-edge coloring of $K_n$ contains either a rainbow (all different colored) copy of $G$ or a…

Combinatorics · Mathematics 2020-01-10 Gyula O. H. Katona , Colton Magnant , Yaping Mao , Zhao Wang

A path in an edge-colored graph is said to be rainbow if no color repeats on it. An edge-colored graph is said to be rainbow $k$-connected if every pair of vertices is connected by $k$ internally disjoint rainbow paths. The rainbow…

Combinatorics · Mathematics 2025-11-19 Igor Araujo , Kareem Benaissa , Richard Bi , Sean English , Shengan Wu , Pai Zheng

A path in an edge-colored graph $G$ is rainbow if no two edges of it are colored the same. The graph $G$ is rainbow-connected if there is a rainbow path between every pair of vertices. If there is a rainbow shortest path between every pair…

Discrete Mathematics · Computer Science 2023-06-22 Melissa Keranen , Juho Lauri

A rainbow path in an edge coloured graph is a path in which no two edges are coloured the same. A rainbow colouring of a connected graph G is a colouring of the edges of G such that every pair of vertices in G is connected by at least one…

Discrete Mathematics · Computer Science 2014-04-18 L. Sunil Chandran , Deepak Rajendraprasad , Marek Tesař

Let $G$ be a nontrivial connected graph with an edge-coloring $c:E(G)\rightarrow \{1,2,\ldots,q\},$ $q\in \mathbb{N}$, where adjacent edges may be colored the same. A tree $T$ in $G$ is a $rainbow tree$ if no two edges of $T$ receive the…

Combinatorics · Mathematics 2013-08-21 Xueliang Li , Kang Yang , Yan Zhao

A path in an edge-colored graph $G$, where adjacent edges may be colored the same, is called a rainbow path if no two edges of $G$ are colored the same. For a $\kappa$-connected graph $G$ and an integer $k$ with $1\leq k\leq \kappa$, the…

Combinatorics · Mathematics 2009-06-23 Xueliang Li , Yuefang Sun

Let $G$ be an edge-colored graph on $n$ vertices. For a vertex $v$, the \emph{color degree} of $v$ in $G$, denoted by $d^c(v)$, is the number of colors appearing on the edges incident with $v$. Denote by $\delta^c(G)=\min\{d^c(v):v\in…

Combinatorics · Mathematics 2025-10-14 Xiaozheng Chen , Bo Ning

For two graphs $G,H$, the \emph{Ramsey number} $r(G,H)$ is the minimum integer $n$ such that any red/blue edge-coloring of $K_n$ contains either a red copy of $G$ or a blue copy of $H$. For two graphs $G,H$, the \emph{Gallai-Ramsey number}…

Combinatorics · Mathematics 2024-01-26 Ping Li , Yaping Mao , Ingo Schiermeyer , Yifan Yao

An edge-colored graph $G$, where adjacent edges may have the same color, is {\it rainbow connected} if every two vertices of $G$ are connected by a path whose edge has distinct colors. A graph $G$ is {\it $k$-rainbow connected} if one can…

Combinatorics · Mathematics 2012-03-15 Hengzhe Li , Xueliang Li , Yuefang Sun , Yan Zhao

Let $k$ be a positive integer, and $G$ be a $k$-connected graph. An edge-coloured path is \emph{rainbow} if all of its edges have distinct colours. The \emph{rainbow $k$-connection number} of $G$, denoted by $rc_k(G)$, is the minimum number…

Combinatorics · Mathematics 2020-09-08 Shinya Fujita , Henry Liu , Boram Park

A Gallai coloring is a coloring of the edges of a complete graph without rainbow triangles, and a Gallai $k$-coloring is a Gallai coloring that uses $k$ colors. We study Ramsey-type problems in Gallai colorings. Given an integer $k\ge1$ and…

Combinatorics · Mathematics 2018-04-03 Christian Bosse , Zi-Xia Song

Given a matroid together with a coloring of its ground set, a subset of its elements is called rainbow colored if no two of its elements have the same color. We show that if a binary matroid of rank $r$ is colored with exactly $r$ colors,…

Combinatorics · Mathematics 2021-09-02 Kristóf Bérczi , Tamás Schwarcz