Results 91 to 100 of about 850,474 (224)
The product structure of squaregraphs
Journal of Graph Theory, Volume 105, Issue 2, Page 179-191, February 2024.Abstract A squaregraph is a plane graph in which each internal face is a 4‐cycle and each internal vertex has degree at least 4. This paper proves that every squaregraph is isomorphic to a subgraph of the semistrong product of an outerplanar graph and a path.
Robert Hickingbotham +3 more
wiley +1 more source
The Cayley Sum Graph of Ideals of a Lattice
Discussiones Mathematicae - General Algebra and Applications, 2020 Let L be a lattice, 𝒥(L) be the set of ideals of L and S be a subset of 𝒥 (L). In this paper, we introduce an undirected Cayley graph of L, denoted by ΓL,S with elements of 𝒥 (L) as the vertex set and, for two distinct vertices I and J, I is adjacent to ...
Afkhami Mojgan +2 more
doaj +1 more source
A note on zero-divisor graph of amalgamated duplication of a ring along an ideal
AKCE International Journal of Graphs and Combinatorics, 2017 Let be a commutative ring and be a non-zero ideal of . Let be the subring of consisting of the elements for and . In this paper we characterize all isomorphism classes of finite commutative rings with identity and ideal such that is planar.
A. Mallika, R. Kala
doaj +1 more source
Crosscap of the non-cyclic graph of groups
AKCE International Journal of Graphs and Combinatorics, 2016 The non-cyclic graph CG to a non locally cyclic group G is as follows: take G∖Cyc(G) as vertex set, where Cyc(G)={x∈G|〈x,y〉 is cyclic for all y∈G} is called the cyclicizer of G, and join two vertices if they do not generate a cyclic subgroup.
K. Selvakumar, M. Subajini
doaj +1 more source
Small Superpatterns for Dominance Drawing
, 2013 We exploit the connection between dominance drawings of directed acyclic graphs and permutations, in both directions, to provide improved bounds on the size of universal point sets for certain types of dominance drawing and on superpatterns for certain ...
Bannister, Michael J. +2 more
core +1 more source
A Survey of Maximal k-Degenerate Graphs and k-Trees
Theory and Applications of GraphsThis article surveys results on maximal $k$-degenerate graphs, $k$-trees, and related classes including simple $k$-trees, $k$-paths, maximal outerplanar graphs, and Apollonian networks.
Allan Bickle
doaj +1 more source
The role of twins in computing planar supports of hypergraphs
, 2020 A support or realization of a hypergraph $H$ is a graph $G$ on the same vertex as $H$ such that for each hyperedge of $H$ it holds that its vertices induce a connected subgraph of $G$.
Kanj, Iyad A. +4 more
core
Reconstruction of maximal outerplanar graphs
Discrete Mathematics, 1972 AbstractS. Ulam has conjectured that every graph with three or more points is uniquely determined by its collection of point-deleted subgraphs. This has been proved for various classes of graphs, but progress has generally been confined to very symmetrical graphs and graphs with connectivity zero or one.
openaire +3 more sources
Minimum rank of outerplanar graphs
Linear Algebra and its Applications, 2012 AbstractThe problem of finding the minimum rank over all symmetric matrices corresponding to a given graph has grown in interest recently. It is well known that the minimum rank of any graph is bounded above by the clique cover number, the minimum number of cliques needed to cover all edges of the graph.
John Sinkovic, Mark Kempton
openaire +2 more sources
Maximum packing for biconnected outerplanar graphs [PDF]
Discrete Applied Mathematics, 1997 A \(G\)-packing of a graph \(H\) is a set of vertex-disjoint subgraphs \(H_{1}, H_{2}, \ldots ,H_{l}\) of \(H\) such that each \(H_{i}\) is isomorphic to \(G\). The problem of maximum \(G\)-packing in \(H\) is to determine the maximum cardinality of a \(G\)-packing of \(H\). In general, the problem is NP-complete, even when \(H\) is a planar graph, and
Tomas Kovac, Andrzej Lingas
openaire +3 more sources