English
Related papers

Related papers: Characterize graphs with rainbow connection number…

200 papers

A path in a vertex-colored graph is a {\it vertex-proper path} if any two internal adjacent vertices differ in color. A vertex-colored graph is {\it proper vertex $k$-connected} if any two vertices of the graph are connected by $k$ disjoint…

Combinatorics · Mathematics 2015-05-20 Hui Jiang , Xueliang Li , Yingying Zhang , Yan Zhao

Let $G$ be a nontrivial connected and vertex-colored graph. A subset $X$ of the vertex set of $G$ is called rainbow if any two vertices in $X$ have distinct colors. The graph $G$ is called \emph{rainbow vertex-disconnected} if for any two…

Combinatorics · Mathematics 2020-06-16 Xueliang Li , Yindi Weng

An edge-coloured path is monochromatic if all of its edges have the same colour. For a $k$-connected graph $G$, the monochromatic $k$-connection number of $G$, denoted by $mc_k(G)$, is the maximum number of colours in an edge-colouring of…

Combinatorics · Mathematics 2024-02-15 Qingqiong Cai , Shinya Fujita , Henry Liu , Boram Park

Let $G$ be a graph of order $n$ with an edge-coloring $c$, and let $\delta^c(G)$ denote the minimum color degree of $G$. A subgraph $F$ of $G$ is called rainbow if all edges of $F$ have pairwise distinct colors. There have been a lot…

Combinatorics · Mathematics 2020-10-23 Xiaozheng Chen , Xueliang Li

A tree in an edge-colored graph $G$ is said to be a rainbow tree if no two edges on the tree share the same color. Given two positive integers $k$, $\ell$ with $k\geq 3$, the \emph{$(k,\ell)$-rainbow index} $rx_{k,\ell}(G)$ of $G$ is the…

Combinatorics · Mathematics 2013-10-21 Qingqiong Cai , Xueliang Li , Jiangli Song

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 heterochromatic (or rainbow) graph is an edge-colored graph whose edges have distinct colors, that is, where each color appears at most once. In this paper, I propose a $(g,f)$-chromatic graph as an edge-colored graph where each color $c$…

Combinatorics · Mathematics 2019-04-15 Kazuhiro Suzuki

A rainbow matching in an edge-coloured graph is a matching such that its edges have distinct colours. We show that every properly edge-coloured graph $G$ with $|G| \ge (9\delta(G) -5)/2$ has a rainbow matching of size $\delta(G)$, improving…

Combinatorics · Mathematics 2011-08-29 Allan Lo

A graph is said to be {\it total-colored} if all the edges and the vertices of the graph is colored. A path in a total-colored graph is a {\it total proper path} if $(i)$ any two adjacent edges on the path differ in color, $(ii)$ any two…

Combinatorics · Mathematics 2015-12-03 Hui Jiang , Xueliang Li , Yingying Zhang

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 $G$ be an edge-colored graph on $n$ vertices. The minimum color degree of $G$, denoted by $\delta^c(G)$, is defined as the minimum number of colors assigned to the edges incident to a vertex in $G$. In 2013, H. Li proved that an…

Combinatorics · Mathematics 2025-10-16 Xueliang Li , Bo Ning , Yongtang Shi , Shenggui Zhang

A graph is said to be \emph{total-colored} if all the edges and the vertices of the graph are colored. A total-colored graph is \emph{total-rainbow connected} if any two vertices of the graph are connected by a path whose edges and internal…

Combinatorics · Mathematics 2017-03-31 Wenjing Li , Xueliang Li , Colton Magnant , Jingshu Zhang

An edge-colored graph $G$ is conflict-free connected if any two of its vertices are connected by a path, which contains a color used on exactly one of its edges. The conflict-free connection number of a connected graph $G$, denoted by…

Combinatorics · Mathematics 2020-12-10 Jing Wang , Meng Ji

Let $G = (G_1, G_2, \ldots, G_m)$ be a collection of $m$ graphs on a common vertex set $V$. For a graph $H$ with vertices in $V$, we say that $G$ contains a rainbow $H$ if there is an injection $c: E(H) \to [m]$ such that for every edge $e…

Combinatorics · Mathematics 2025-12-16 Yupei Li , Ruth Luo

An edge-coloured graph $G$ is called $properly$ $connected$ if every two vertices are connected by a proper path. The $proper$ $connection$ $number$ of a connected graph $G$, denoted by $pc(G)$, is the smallest number of colours that are…

Combinatorics · Mathematics 2018-06-26 Xiaxia Guan , Lina Xue , Eddie Cheng , Weihua Yang

Let $G$ be a connected graph. The \emph{rainbow connection number $rc(G)$} of a graph $G$ was recently introduced by Chartrand et al. Li et al. proved that for every bridgeless graph $G$ with diameter 2, $rc(G)\leq 5$. They gave examples…

Combinatorics · Mathematics 2011-09-26 Jiuying Dong , Xueliang Li

Let $G$ be an edge-colored connected graph. A path $P$ in $G$ is called a distance $\ell$-proper path if no two edges of the same color appear with fewer than $\ell$ edges in between on $P$. The graph $G$ is called $(k,\ell)$-proper…

Combinatorics · Mathematics 2016-06-22 Xueliang Li , Colton Magnant , Meiqin Wei , Xiaoyu Zhu

A path $P$ in an edge-colored graph $G$ is called \emph{a proper path} if no two adjacent edges of $P$ are colored the same, and $G$ is \emph{proper connected} if every two vertices of $G$ are connected by a proper path in $G$. The…

Combinatorics · Mathematics 2015-05-12 Yaping Mao , Fengnan Yanling , Zhao Wang , Chengfu Ye

We say that a graph $G$ is $(2,m)$-linked if, for any distinct vertices $a_1,\ldots, a_m, b_1,b_2$ in $G$, there exist vertex disjoint connected subgraphs $A,B$ of $G$ such that $\{a_1, \ldots, a_m\}$ is contained in $A$ and $\{b_1,b_2\}$…

Combinatorics · Mathematics 2023-03-23 Xiying Du , Yanjia Li , Shijie Xie , Xingxing Yu

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