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Related papers: Weighted Well-Covered Claw-Free Graphs

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We define a perfect coloring of a graph $G$ as a proper coloring of $G$ such that every connected induced subgraph $H$ of $G$ uses exactly $\omega(H)$ many colors where $\omega(H)$ is the clique number of $H$. A graph is perfectly colorable…

Combinatorics · Mathematics 2011-08-15 R B Sandeep

We give alternative definitions for maximum matching width, e.g. a graph $G$ has $\operatorname{mmw}(G) \leq k$ if and only if it is a subgraph of a chordal graph $H$ and for every maximal clique $X$ of $H$ there exists $A,B,C \subseteq X$…

Data Structures and Algorithms · Computer Science 2015-07-10 Jisu Jeong , Sigve Hortemo Sæther , Jan Arne Telle

A graph $G$ is said to be equitably $c$-colorable if its vertices can be partitioned into $c$ independent sets that pairwise differ in size by at most one. Chen, Lih, and Wu conjectured that every connected graph $G$ with maximum degree…

Combinatorics · Mathematics 2025-03-04 James M. Shook

Let G=(V,E) be a graph with f:V\to Z_+ a function assigning degree bounds to vertices. We present the first efficient algebraic algorithm to find an f-factor. The time is \tilde{O}(f(V)^{\omega}). More generally for graphs with integral…

Data Structures and Algorithms · Computer Science 2013-04-26 Harold N. Gabow , Piotr Sankowski

We discuss how to find the well-covered dimension of a graph that is the Cartesian product of paths, cycles, complete graphs, and other simple graphs. Also, a bound for the well-covered dimension of $K_n\times G$ is found, provided that $G$…

Combinatorics · Mathematics 2015-03-13 Isaac Birnbaum , Megan Kuneli , Robyn McDonald , Katherine Urabe , Oscar Vega

The Perfect Graph Theorems are important results in graph theory describing the relationship between clique number $\omega(G) $ and chromatic number $\chi(G) $ of a graph $G$. A graph $G$ is called \emph{perfect} if $\chi(H)=\omega(H)$ for…

Logic in Computer Science · Computer Science 2019-12-06 Abhishek Kr Singh , Raja Natarajan

A {\it star-factor} of a graph $G$ is a spanning subgraph of $G$ such that each component of which is a star. An {\it edge-weighting} of $G$ is a function $w: E(G)\longrightarrow \mathbb{N}^+$, where $\mathbb{N}^+$ is the set of positive…

Combinatorics · Mathematics 2007-07-03 Yunjian Wu , Qinglin Yu

We show that the dominating set problem parameterized by solution size is fixed-parameter tractable (FPT) in graphs that do not contain the claw (K(1,3)), the complete bipartite graph on four vertices where the two parts have one and three…

Data Structures and Algorithms · Computer Science 2015-03-17 Marek Cygan , Geevarghese Philip , Marcin Pilipczuk , Michał Pilipczuk , Jakub Onufry Wojtaszczyk

In a finite undirected graph $G=(V,E)$, a vertex $v \in V$ {\em dominates} itself and its neighbors in $G$. A vertex set $D \subseteq V$ is an {\em efficient dominating set} ({\em e.d.} for short) of $G$ if every $v \in V$ is dominated in…

Discrete Mathematics · Computer Science 2015-09-15 Andreas Brandstadt , Raffaele Mosca

We say that a graph $G$ on $n$ vertices is $\{H,F\}$-$o$-heavy if every induced subgraph of $G$ isomorphic to $H$ or $F$ contains two nonadjacent vertices with degree sum at least $n$. Generalizing earlier sufficient forbidden subgraph…

Combinatorics · Mathematics 2024-09-23 Wangyi Shang , Hajo Broersma , Shenggui Zhang , Binlong Li

A complete graph is the graph in which every two vertices are adjacent. For a graph $G=(V,E)$, the complete width of $G$ is the minimum $k$ such that there exist $k$ independent sets $\mathtt{N}_i\subseteq V$, $1\le i\le k$, such that the…

Discrete Mathematics · Computer Science 2016-12-28 Van Bang Le , Sheng-Lung Peng

A set of edges $F$ in a graph $G$ is an edge dominating set if every edge in $G$ is either in $F$ or shares a vertex with an edge in $F$. $G$ is said to be well-edge-dominated if all of its minimal edge dominating sets have the same…

Combinatorics · Mathematics 2024-12-17 Jake Berg , Perryn Chang , Claire Kaneshiro , Kirsti Kuenzel , Ryan Pellico , Isabel Renteria , Sumi Vora

A graph is called equimatchable if all of its maximal matchings have the same size. Due to Eiben and Kotrb\v{c}\'{i}k,, any connected graph with odd order and independence number $\alpha(G)$ at most $2$ is equimatchable. Akbari et al.…

Combinatorics · Mathematics 2025-09-15 Xiao Zhao , Haojie Zheng , Fengming Dong , Hengzhe Li , Yingbin Ma

A connected partition is a partition of the vertices of a graph into sets that induce connected subgraphs. Such partitions naturally occur in many application areas such as road networks, and image processing. We consider Balanced Connected…

For an integer $t$, a graph $G$ is called {\em{$C_{>t}$-free}} if $G$ does not contain any induced cycle on more than~$t$ vertices. We prove the following statement: for every pair of integers $d$ and $t$ and a CMSO$_2$ statement~$\phi$,…

Data Structures and Algorithms · Computer Science 2021-01-13 Peter Gartland , Daniel Lokshtanov , Marcin Pilipczuk , Michal Pilipczuk , Pawel Rzazewski

A connected matching in a graph G consists of a set of pairwise disjoint edges whose covered vertices induce a connected subgraph of G. While finding a connected matching of maximum cardinality is a well-solved problem, it is NP-hard to…

Discrete Mathematics · Computer Science 2024-08-12 Phillippe Samer , Phablo F. S. Moura

A graph $G$ is called matching covered if all of its edges are contained in some perfect matching of $G$. Furthermore, a cycle $C \subseteq G$ is called conformal if $G - V(C)$ has a perfect matching and $G$ itself is called cycle-conformal…

Combinatorics · Mathematics 2026-02-10 Maximilian Gorsky , Clemens Kuske

If for any $k$ the $k$-th coefficient of a polynomial I(G;x) is equal to the number of stable sets of cardinality $k$ in graph $G$, then it is called the independence polynomial of $G$ (Gutman and Harary, 1983). J. I. Brown, K. Dilcher and…

Combinatorics · Mathematics 2007-05-23 Vadim E. Levit , Eugen Mandrescu

For a graph $G$, let $f_o(G)$ denote the maximum order of an induced subgraph of $G$ all of whose vertices have odd degree, and let $\chi(G)$ denote the chromatic number of $G$. Scott (CPC, 1992) proved that $f_o(G) \ge |V(G)|/(2\chi(G))$…

Combinatorics · Mathematics 2026-04-22 Bo Ning

We call a (simple) graph G codismantlable if either it has no edges or else it has a codominated vertex x, meaning that the closed neighborhood of x contains that of one of its neighbor, such that G-x codismantlable. We prove that if G is…

Combinatorics · Mathematics 2014-01-22 Turker Biyikoglu , Yusuf Civan