Results 41 to 50 of about 231 (167)

The Planar Index and Outerplanar Index of Some Graphs Associated to Commutative Rings

open access: yesDiscussiones Mathematicae - General Algebra and Applications, 2019
In this paper, we study the planar and outerplanar indices of some graphs associated to a commutative ring. We give a full characterization of these graphs with respect to their planar and outerplanar indices when R is a finite ring.
Barati Zahra, Afkhami Mojgan
doaj   +1 more source

Outerplanar Graphs and Delaunay Triangulations [PDF]

open access: yes, 2012
Dillencourt [1] showed that all maximal outerplanar graphs can be realized as Delaunay triangulations of points in convex position. In this note, we give two new, alternate proofs.
Alam, Ashraful   +2 more
openaire   +2 more sources

Outerplanar Graph Drawings with Few Slopes [PDF]

open access: yesComputational Geometry, 2012
Major revision of the whole ...
Kolja B. Knauer   +2 more
openaire   +6 more sources

Drawing Outer 1-planar Graphs with Few Slopes

open access: yesJournal of Graph Algorithms and Applications, 2015
A graph is outer 1-planar if it admits a drawing where each vertex is on the outer face and each edge is crossed by at most another edge. Outer 1-planar graphs are a superclass of the outerplanar graphs and a subclass of the planar partial 3-trees.
Emilio Di Giacomo   +2 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

Nilpotent graphs with crosscap at most two

open access: yesAKCE International Journal of Graphs and Combinatorics, 2018
Let be a commutative ring with identity. The nilpotent graph of , denoted by , is a graph with vertex set , and two vertices and are adjacent if and only if is nilpotent, where .
A. Mallika, R. Kala
doaj   +1 more source

Directed Acyclic Outerplanar Graphs Have Constant Stack Number [PDF]

open access: yesTheoretiCS
The stack number of a directed acyclic graph $G$ is the minimum $k$ for which there is a topological ordering of $G$ and a $k$-coloring of the edges such that no two edges of the same color cross, i.e., have alternating endpoints along the topological ...
Paul Jungeblut   +2 more
doaj   +1 more source

A Polynomial-Time Algorithm for Computing the Maximum Common Connected Edge Subgraph of Outerplanar Graphs of Bounded Degree

open access: yesAlgorithms, 2013
The maximum common connected edge subgraph problem is to find a connected graph with the maximum number of edges that is isomorphic to a subgraph of each of the two input graphs, where it has applications in pattern recognition and chemistry.
Takeyuki Tamura, Tatsuya Akutsu
doaj   +1 more source

Perfect Matching Under Precedence Constraints

open access: yesNetworks, Volume 87, Issue 2, Page 175-190, March 2026.
ABSTRACT In this article, we motivate and define variants of perfect matching under precedence constraints where a perfect matching is built incrementally and precedence constraints ensure that an edge may only be added to the matching if the edge's predecessor vertices have already been covered.
Christina Büsing, Corinna Mathwieser
wiley   +1 more source

On Large Induced Outerplanar Subgraphs in $2$-Outerplanar Graphs

open access: yesCoRR
Borradaile, Le and Sherman-Bennett [Graphs and Combinatorics, 2017] proved that every $n$-vertex $2$-outerplane graph has a set of at least $2n/3$ vertices that induces an outerplane graph. We identify a major flaw in their proof and recover their result with a different, and unfortunately much more complex, proof.
Marco D'Elia, Fabrizio Frati
openaire   +2 more sources

Home - About - Disclaimer - Privacy