English
Related papers

Related papers: More on rainbow disconnection in graphs

200 papers

Given a graph $G$ and a subgraph $H$ of $G$, let $rb(G,H)$ be the minimum number $r$ for which any edge-coloring of $G$ with $r$ colors has a rainbow subgraph $H$. The number $rb(G,H)$ is called the rainbow number of $H$ with respect to…

Combinatorics · Mathematics 2007-11-20 Xueliang Li , Zhixia Xu

In an edge-colored graph $G$, a rainbow clique $K_k$ is a $k$-complete subgraph in which all the edges have distinct colors. Let $e(G)$ and $c(G)$ be the number of edges and colors in $G$, respectively. In this paper, we show that for any…

Combinatorics · Mathematics 2023-08-16 Xiao-Chuan Liu , Danni Peng , Xu Yang

A subgraph of an edge-coloured graph is called rainbow if all its edges have different colours. We prove a rainbow version of the blow-up lemma of Koml\'os, S\'ark\"ozy and Szemer\'edi that applies to almost optimally bounded colourings. A…

Combinatorics · Mathematics 2019-07-24 Stefan Ehard , Stefan Glock , Felix Joos

In this paper we study the following problem proposed by Barrus, Ferrara, Vandenbussche, and Wenger. Given a graph $H$ and an integer $t$, what is $\operatorname{sat}_{t}\left(n, \mathfrak{R}{(H)}\right)$, the minimum number of edges in a…

Combinatorics · Mathematics 2019-10-24 António Girão , David Lewis , Kamil Popielarz

The proper connection number $pc(G)$ of a connected graph $G$ is defined as the minimum number of colors needed to color its edges, so that every pair of distinct vertices of $G$ is connected by at least one path in $G$ such that no two…

Combinatorics · Mathematics 2015-01-26 Xueliang Li , Meiqin Wei , Jun Yue

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 \emph{uniform random intersection graph} $G(n,m,k)$ is a random graph constructed as follows. Label each of $n$ nodes by a randomly chosen set of $k$ distinct colours taken from some finite set of possible colours of size $m$. Nodes are…

Combinatorics · Mathematics 2008-12-03 Simon R. Blackburn , Stefanie Gerke

A rainbow neighbourhood of a graph $G$ with respect to a proper colouring $\C$ of $G$ is the closed neighbourhood $N[v]$ of a vertex $v$ in $G$ such that $N[v]$ consists of vertices from all colour classes in $G$ with respect to $\C$. The…

General Mathematics · Mathematics 2017-10-03 Johan Kok , Sudev Naduvath , Orville Buelban

In this paper, we consider rainbow connection number of maximal outerplanar graphs(MOPs) on algorithmic aspect. For the (MOP) $G$, we give sufficient conditions to guarantee that $rc(G) = diam(G).$ Moreover, we produce the graph with given…

Combinatorics · Mathematics 2016-05-09 Xingchao Deng , Hengzhe Li , Guiying Yan

An $r$-regular graph is an $r$-graph, if every odd set of vertices is connected to its complement by at least $r$ edges. Let $G$ and $H$ be $r$-graphs. An $H$-coloring of $G$ is a mapping $f\colon E(G) \to E(H)$ such that each $r$ adjacent…

Combinatorics · Mathematics 2023-05-16 Yulai Ma , Davide Mattiolo , Eckhard Steffen , Isaak H. Wolf

We consider the following random model for edge-colored graphs. A graph $G$ on $n$ vertices is fixed, and a random subgraph $G_p$ is chosen by letting each edge of $G$ remain independently with probability $p$. Then, each edge of $G_p$ is…

Combinatorics · Mathematics 2023-01-10 Peter Bradshaw

The resistance $r(G)$ of a graph $G$ is the minimum number of edges that have to be removed from $G$ to obtain a graph which is $\Delta(G)$-edge-colorable. The paper relates the resistance to other parameters that measure how far is a graph…

Discrete Mathematics · Computer Science 2011-11-17 Vahan Mkrtchyan , Eckhard Steffen

Let $G$ be a (multi)graph of order $n$ and let $u,v$ be vertices of $G$. The maximum number of internally disjoint $u$-$v$ paths in $G$ is denoted by $\kappa_G(u,v)$, and the maximum number of edge-disjoint $u$-$v$ paths in $G$ is denoted…

Combinatorics · Mathematics 2018-10-25 Rocío M. Casablanca , Lucas Mol , Ortrud R. Oellermann

A {\it rainbow matching} in an edge-colored graph is a matching in which all the edges have distinct colors. Wang asked if there is a function f(\delta) such that a properly edge-colored graph G with minimum degree \delta and order at least…

Combinatorics · Mathematics 2011-08-15 Jennifer Diemunsch , Michael Ferrara , Casey Moffatt , Florian Pfender , Paul S. Wenger

We say that $k$ graphs $G_1,G_2,\dots,G_k$ on a common vertex set of size $n$ contain a rainbow copy of a graph $H$ if their union contains a copy of $H$ with each edge belonging to a distinct $G_i$. We provide a counterexample to a…

Combinatorics · Mathematics 2022-11-15 Peter Frankl , Ervin Győri , Zhen He , Zequn Lv , Nika Salia , Casey Tompkins , Kitti Varga , Xiutao Zhu

An edge subset \( S \subseteq E(G) \) is called a 3-restricted edge-cut if \( G - S \) is disconnected and each component of \( G - S \) contains at least three vertices. The 3-restricted edge-connectivity of a graph \( G \), denoted by \(…

Combinatorics · Mathematics 2025-12-01 Wenxin Wang , Yingzhi Tian

An edge-coloured graph $G$ is {\it rainbow connected} if any two vertices are connected by a path whose edges have distinct colours. This concept was introduced by Chartrand et al. in \cite{ch01}, and it was extended to oriented graphs by…

Combinatorics · Mathematics 2015-04-08 Jesús Alva-Samos , Juan José Montellano-Ballesteros

An edge-colored graph $G$ is called properly colored if no two adjacent edges share a color in $G$. An edge-colored connected graph $G$ is called properly connected if between every pair of distinct vertices, there exists a path that is…

Combinatorics · Mathematics 2019-03-11 Shinya Fujita

An edge-coloring of a graph $H$ is a function $\mathcal{C}: E(H) \rightarrow \mathbb{N}$. We say that $H$ is rainbow if all edges of $H$ have different colors. Given a graph $F$, an edge-colored graph $G$ is $F$-rainbow saturated if $G$…

Combinatorics · Mathematics 2025-01-14 Yiduo Xu , Zhen He , Mei Lu

Let $G$ be a graph and $f:V(G)\rightarrow \mathbb{N}$ be a function. An $f$-coloring of a graph $G$ is an edge coloring such that each color appears at each vertex $v\in V(G)$ at most $f (v)$ times. The minimum number of colors needed to…

Combinatorics · Mathematics 2015-01-20 S. Akbari , M. Chavooshi , M. Ghanbari , R. Manaviyat
‹ Prev 1 8 9 10 Next ›