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Edge-group choosability of outerplanar and near-outerplanar graphs [PDF]

open access: yesTransactions on Combinatorics, 2020
Let $\chi_{gl}(G)$ be the {\it{group choice number}} of $G$. A graph $G$ is called {\it{edge-$k$-group choosable}} if its line graph is $k$-group choosable. The {\it{group-choice index}} of $G$, $\chi'_{gl}(G)$, is the smallest $k$ such that $G$ is edge-$
Amir Khamseh
doaj   +1 more source

Circular Separation Dimension of a Subclass of Planar Graphs [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2017
A pair of non-adjacent edges is said to be separated in a circular ordering of vertices, if the endpoints of the two edges do not alternate in the ordering.
Arpitha P. Bharathi   +2 more
doaj   +1 more source

On the planarity of line Mycielskian graph of a graph

open access: yesRatio Mathematica, 2020
The line Mycielskian graph of a graph G, denoted by Lμ(G) is defined as the graph obtained from L(G) by adding q+1 new vertices E' = ei' : 1 ≤  i ≤  q and e, then for 1 ≤  i ≤  q , joining ei' to the neighbours of ei  and  to e.
Keerthi G. Mirajkar   +1 more
doaj   +1 more source

Double domination in maximal outerplanar graphs

open access: yesOpen Mathematics, 2022
In graph GG, a vertex dominates itself and its neighbors. A subset S⊆V(G)S\subseteq V\left(G) is said to be a double-dominating set of GG if SS dominates every vertex of GG at least twice.
Zhuang Wei, Zheng Qiuju
doaj   +1 more source

On the spread of outerplanar graphs

open access: yesSpecial Matrices, 2022
The spread of a graph is the difference between the largest and most negative eigenvalue of its adjacency matrix. We show that for sufficiently large nn, the nn-vertex outerplanar graph with maximum spread is a vertex joined to a linear forest with Ω(n ...
Gotshall Daniel   +2 more
doaj   +1 more source

Algorithms for Outerplanar Graph Roots and Graph Roots of Pathwidth at Most 2 [PDF]

open access: yesAlgorithmica, 2017
Deciding if a graph has a square root is a classical problem, which has been studied extensively both from graph-theoretic and algorithmic perspective. As the problem is NP-complete, substantial effort has been dedicated to determining the complexity of ...
P. Golovach   +4 more
semanticscholar   +1 more source

The Singularity of Oriented Outerplanar Graphs with a Given Number of Inner Edges

open access: yesJournal of Mathematics, 2022
A digraph is called oriented if there is at most one arc between two distinct vertices. An oriented graph is called nonsingular (singular) if its adjacency matrix AD is nonsingular (singular).
Borui He, Xianya Geng, Long Wang
doaj   +1 more source

Strong Chromatic Index of Outerplanar Graphs

open access: yesAxioms, 2022
The strong chromatic index χs′(G) of a graph G is the minimum number of colors needed in a proper edge-coloring so that every color class induces a matching in G. It was proved In 2013, that every outerplanar graph G with Δ≥3 has χs′(G)≤3Δ−3.
Ying Wang   +3 more
doaj   +1 more source

Optimal maximal graphs [PDF]

open access: yesTransactions on Combinatorics, 2022
An optimal labeling of a graph with $n$ vertices and $m$ edges is an injective assignment of the first $n$ nonnegative integers to the vertices‎, ‎that induces‎, ‎for each edge‎, ‎a weight given by the sum of the labels of its end-vertices with the ...
Christian Barrientos, Maged Youssef
doaj   +1 more source

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