Results 21 to 30 of about 908,928 (292)

A Short Proof of the Size of Edge-Extremal Chordal Graphs

open access: yesJournal of Mathematical Sciences and Modelling, 2022
[3] have recently determined the maximum number of edges of a chordal graph with a maximum degree less than $d$ and the matching number at most $\nu$ by exhibiting a family of chordal graphs achieving this bound. We provide simple proof of their result.
Mordechai Shalom
doaj   +1 more source

A biased random-key genetic algorithm for the chordal completion problem

open access: yesRAIRO Oper. Res., 2023
A graph is chordal if all its cycles of length greater than or equal to four contain a chord, i.e., an edge connecting two nonconsecutive vertices of the cycle.
S. E. Silva   +2 more
semanticscholar   +1 more source

Semipaired Domination in Some Subclasses of Chordal Graphs [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2021
A dominating set $D$ of a graph $G$ without isolated vertices is called semipaired dominating set if $D$ can be partitioned into $2$-element subsets such that the vertices in each set are at distance at most $2$. The semipaired domination number, denoted
Michael A. Henning   +2 more
doaj   +1 more source

Efficient (j, k)-Dominating Functions

open access: yesDiscussiones Mathematicae Graph Theory, 2023
For positive integers j and k, an efficient (j, k)-dominating function of a graph G = (V, E) is a function f : V → {0, 1, 2, . . ., j} such that the sum of function values in the closed neighbourhood of every vertex equals k. The relationship between the
Klostermeyer William F.   +3 more
doaj   +1 more source

MAT-free graphic arrangements and a characterization of strongly chordal graphs by edge-labeling [PDF]

open access: yesAlgebraic Combinatorics, 2022
Ideal subarrangements of a Weyl arrangement are proved to be free by the multiple addition theorem (MAT) due to Abe-Barakat-Cuntz-Hoge-Terao (2016). They form a significant class among Weyl subarrangements that are known to be free so far. The concept of
T. Tran, S. Tsujie
semanticscholar   +1 more source

Transitivity on subclasses of chordal graphs [PDF]

open access: yesInternational Conference on Algorithms and Discrete Applied Mathematics, 2022
Let $G=(V, E)$ be a graph, where $V$ and $E$ are the vertex and edge sets, respectively. For two disjoint subsets $A$ and $B$ of $V$, we say $A$ \textit{dominates} $B$ if every vertex of $B$ is adjacent to at least one vertex of $A$ in $G$.
S. Paul, Kamal Santra
semanticscholar   +1 more source

On the End-Vertex Problem of Graph Searches [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2019
End vertices of graph searches can exhibit strong structural properties and are crucial for many graph algorithms. The problem of deciding whether a given vertex of a graph is an end-vertex of a particular search was first introduced by Corneil, K\"ohler
Jesse Beisegel   +6 more
doaj   +1 more source

Chordal multipartite graphs and chordal colorings

open access: bronzeDiscrete Mathematics, 2007
Abstract‘Chordal multipartite graphs’ are properly colored graphs such that two vertices in a minimal vertex separator are adjacent if and only if they are differently colored. They have induced cycle characterizations that transcend those of chordal and chordal bipartite graphs.
Terry A. McKee
openalex   +3 more sources

Minimal toughness in special graph classes [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2023
Let $t$ be a positive real number. A graph is called $t$-tough if the removal of any vertex set $S$ that disconnects the graph leaves at most $|S|/t$ components, and all graphs are considered 0-tough. The toughness of a graph is the largest $t$ for which
Gyula Y. Katona, Kitti Varga
doaj   +1 more source

Polynomial kernels for edge modification problems towards block and strictly chordal graphs [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science
We consider edge modification problems towards block and strictly chordal graphs, where one is given an undirected graph $G = (V,E)$ and an integer $k \in \mathbb{N}$ and seeks to edit (add or delete) at most $k$ edges from $G$ to obtain a block graph or
Maël Dumas   +3 more
doaj   +1 more source

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