Results 71 to 80 of about 584,165 (157)
Edge covering pseudo-outerplanar graphs with forests [PDF]
A graph is pseudo-outerplanar if each block has an embedding on the plane in such a way that the vertices lie on a fixed circle and the edges lie inside the disk of this circle with each of them crossing at most one another.
Zhang, Xin, Liu, Guizhen, Wu, Jian-Liang
core +1 more source
On tree decompositions whose trees are minors
Abstract In 2019, Dvořák asked whether every connected graph G $G$ has a tree decomposition ( T , B ) $(T,{\rm{ {\mathcal B} }})$ so that T $T$ is a subgraph of G $G$ and the width of ( T , B ) $(T,{\rm{ {\mathcal B} }})$ is bounded by a function of the treewidth of G $G$.
Pablo Blanco +5 more
wiley +1 more source
Star Coloring Outerplanar Bipartite Graphs
A proper coloring of the vertices of a graph is called a star coloring if at least three colors are used on every 4-vertex path. We show that all outerplanar bipartite graphs can be star colored using only five colors and construct the smallest known ...
Ramamurthi Radhika, Sanders Gina
doaj +1 more source
Approximation Algorithms for the Maximum Induced Planar and Outerplanar Subgraph Problems
The task of finding the largest subset of vertices of a graph that induces a planar subgraph is known as the Maximum Induced Planar Subgraph problem (MIPS). In this paper, some new approximation algorithms for MIPS are introduced.
Kerri Morgan, Graham Farr
doaj +1 more source
The product structure of squaregraphs
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
On Vertices Enforcing a Hamiltonian Cycle
A nonempty vertex set X ⊆ V (G) of a hamiltonian graph G is called an H-force set of G if every X-cycle of G (i.e. a cycle of G containing all vertices of X) is hamiltonian.
Fabrici Igor +2 more
doaj +1 more source
Maximal outerplanar graphs as chordal graphs, path-neighborhood graphs, and triangle graphs [PDF]
Maximal outerplanar graphs are characterized using three different classes of graphs. A path-neighborhood graph is a connected graph in which every neighborhood induces a path. The triangle graph $T(G)$ has the triangles of the graph $G$ as its vertices,
Novick, B., Laskar, R.C., Mulder, H.M.
core
Upward Planarity Testing of Outerplanar Dags (Extended Abstract)
In this paper, we present two polynomial-time algorithms to determine if an outerplanar directed acyclic graph (odag) can be drawn upward planar, that is, drawn in planar straight-line fashion so that all arcs point up.
Papakostas, Achilleas +1 more
core +1 more source
Improved Bounds for Track Numbers of Planar Graphs
A track layout of a graph consists of a vertex coloring and a total order of each color class, such that no two edges cross between any two color classes.
Sergey Pupyrev
doaj +1 more source
A fast parallel algorithm for optimal edge-colouring of outerplanar graphs [PDF]
We prove that every outerplanar graph can be optimally edge-coloured in polylog time using a polynomial number of processors on a parallel random access machine without write conflicts (P-RAM)
Gibbons, Alan (Alan M.) +1 more
core

