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An edge weighting problem of a graph G is an assignment of an integer weight to each edge e. Based on edge weighting problem, several types of vertex-coloring problems are put forward. A simple observation illuminates that edge weighting…

Combinatorics · Mathematics 2010-07-09 Yinghua Duan , Hongliang Lu , Qinglin yu

Given a graph $G$, a proper $k$-coloring of $G$ is a partition $c = (S_i)_{i\in [1,k]}$ of $V(G)$ into $k$ stable sets $S_1,\ldots, S_{k}$. Given a weight function $w: V(G) \to \mathbb{R}^+$, the weight of a color $S_i$ is defined as $w(i)…

Data Structures and Algorithms · Computer Science 2018-05-18 Júlio Araújo , Victor A. Campos , Carlos Vinícius G. C. Lima , Vinícius Fernandes dos Santos , Ignasi Sau , Ana Silva

Let (G,w) be a weighted graph. The necessary and sufficient conditions under which a weight w : E(G)-->R^+ can be extended to a pseudoultrametric on V(G) are found. A criterion of the uniqueness of this extension is also obtained. It is…

Metric Geometry · Mathematics 2011-11-01 O. Dovgoshey , E. Petrov

A graph G is well-covered if all its maximal independent sets are of the same cardinality. Assume that a weight function w is defined on its vertices. Then G is w-well-covered if all maximal independent sets are of the same weight. For…

Discrete Mathematics · Computer Science 2012-10-26 Vadim Levit , David Tankus

A total weighting of a graph $G$ is a mapping $f$ which assigns to each element $z \in V(G) \cup E(G)$ a real number $f(z)$ as its weight. The vertex sum of $v$ with respect to $f$ is $\phi_f(v)=\sum_{e \in E(v)}f(e)+f(v)$. A total…

Combinatorics · Mathematics 2015-10-06 Tsai-Lien Wong , Xuding Zhu

Let ${\cal G}=(G,w) $ be a positive-weighted graph, that is a graph $G$ endowed with a function $w$ from the edge set of $G$ to the set of positive real numbers; for any distinct vertices $i,j $, we define $D_{i,j}({\cal G})$ to be the…

Combinatorics · Mathematics 2016-05-04 Agnese Baldisserri , Elena Rubei

A graph $G$ is well-covered if all its maximal independent sets are of the same cardinality. Assume that a weight function $w$ is defined on its vertices. Then $G$ is $w$-well-covered if all maximal independent sets are of the same weight.…

Discrete Mathematics · Computer Science 2018-11-13 Vadim E. Levit , David Tankus

For a graph $G$ with a given list assignment $L$ on the vertices, we give an algebraical description of the set of all weights $w$ such that $G$ is $(L,w)$-colorable, called permissible weights. Moreover, for a graph $G$ with a given list…

Combinatorics · Mathematics 2013-03-21 Yves Aubry , Jean-Christophe Godin , Olivier Togni

A graph $G$ is well-covered if all maximal independent sets are of the same cardinality. Let $w:V(G) \longrightarrow\mathbb{R}$ be a weight function. Then $G$ is $w$-well-covered if all maximal independent sets are of the same weight. An…

Combinatorics · Mathematics 2024-03-25 Vadim E. Levit , David Tankus

Given a complete graph with positive weights on its edges, we define the weight of a subset of edges as the product of weights of the edges in the subset and consider sums (partition functions) of weights over subsets of various kinds:…

Combinatorics · Mathematics 2013-05-14 Alexander Barvinok

This paper focuses on extensions of the classic Erd\H{o}s-Gallai Theorem for the set of weighted function of each edge in a graph. The weighted function of an edge $e$ of an $n$-vertex uniform hypergraph $\mathcal{H}$ is defined to a…

Combinatorics · Mathematics 2024-04-02 Kai Zhao , Xiao-Dong Zhang

Let {\cal G}=(G,w) be a positive-weighted simple finite graph, that is, let G be a simple finite graph endowed with a function w from the set of the edges of G to the set of the positive real numbers. For any subgraph G' of G, we define…

Combinatorics · Mathematics 2013-02-05 Agnese Baldisserri , Elena Rubei

A subset $I$ of the vertex set $V(G)$ of a graph $G$ is called a $k$-clique independent set of $G$ if no $k$ vertices in $I$ form a $k$-clique of $G$. An independent set is a $2$-clique independent set. Let $\pi_k(G)$ denote the number of…

Combinatorics · Mathematics 2024-01-02 Peter Borg , Carl Feghali , Rémi Pellerin

Suppose you are given a graph $G=(V,E)$ with a weight assignment $w:V\rightarrow\mathbb{Z}$ and that your objective is to modify $w$ using legal steps such that all vertices will have the same weight, where in each legal step you are…

Discrete Mathematics · Computer Science 2015-07-03 Friedrich Eisenbrand , Shay Moran , Rom Pinchasi , Martin Skutella

A $t$-tone $k$-coloring of $G$ assigns to each vertex of $G$ a set of $t$ colors from $\{1,..., k\}$ so that vertices at distance $d$ share fewer than $d$ common colors. The {\it $t$-tone chromatic number} of $G$, denoted $\tau_t(G)$, is…

Combinatorics · Mathematics 2015-08-06 Daniel W. Cranston , Jaehoon Kim , William B. Kinnersley

A total weighting of the vertices and edges of a hypergraph is called vertex-coloring if the total weights of the vertices yield a proper coloring of the graph, i.e., every edge contains at least two vertices with different weighted…

Combinatorics · Mathematics 2013-12-24 Florian Pfender

Consider a weighted graph G with n vertices, numbered by the set {1,...,n}. For any path p in G, we call w_G(p) the sum of the weights of the edges of the path and we define the multiset {\cal D}_{i,j} (G) = {w_G(p) | p simple path between…

Combinatorics · Mathematics 2012-10-03 Elena Rubei

Motivated by the analysis of consensus formation in the Deffuant model for social interaction, we consider the following procedure on a graph $G$. Initially, there is one unit of tea at a fixed vertex $r \in V(G)$, and all other vertices…

Let $G=(V,E,w)$ be a finite, connected graph with weighted edges. We are interested in the problem of finding a subset $W \subset V$ of vertices and weights $a_w$ such that $$ \frac{1}{|V|}\sum_{v \in V}^{}{f(v)} \sim \sum_{w \in W}{a_w…

Statistics Theory · Mathematics 2018-03-20 George C. Linderman , Stefan Steinerberger

Let $A$ and $B$ be sets of vertices in a graph $G$. Menger's theorem states that for every positive integer $k$, either there exists a collection of $k$ vertex-disjoint paths between $A$ and $B$, or $A$ can be separated from $B$ by a set of…

Combinatorics · Mathematics 2023-09-18 Peter Gartland , Tuukka Korhonen , Daniel Lokshtanov