Results 31 to 40 of about 1,772 (132)

Game Chromatic Number of Generalized Petersen Graphs and Jahangir Graphs

open access: yesJournal of Applied Mathematics, Volume 2020, Issue 1, 2020., 2020
Let G = (V, E) be a graph, and two players Alice and Bob alternate turns coloring the vertices of the graph G a proper coloring where no two adjacent vertices are signed with the same color. Alice′s goal is to color the set of vertices using the minimum number of colors, which is called game chromatic number and is denoted by χg(G), while Bob′s goal is
Ramy Shaheen   +3 more
wiley   +1 more source

Track Layouts of Graphs [PDF]

open access: yes, 2004
A \emph{$(k,t)$-track layout} of a graph $G$ consists of a (proper) vertex $t$-colouring of $G$, a total order of each vertex colour class, and a (non-proper) edge $k$-colouring such that between each pair of colour classes no two monochromatic edges ...
Dujmovic, Vida   +2 more
core   +5 more sources

Faster Algorithms for the Maximum Common Subtree Isomorphism Problem [PDF]

open access: yes, 2016
The maximum common subtree isomorphism problem asks for the largest possible isomorphism between subtrees of two given input trees. This problem is a natural restriction of the maximum common subgraph problem, which is ${\sf NP}$-hard in general graphs ...
Droschinsky, Andre   +2 more
core   +2 more sources

Vertex Colorings without Rainbow Subgraphs

open access: yesDiscussiones Mathematicae Graph Theory, 2016
Given a coloring of the vertices of a graph G, we say a subgraph is rainbow if its vertices receive distinct colors. For a graph F, we define the F-upper chromatic number of G as the maximum number of colors that can be used to color the vertices of G ...
Goddard Wayne, Xu Honghai
doaj   +1 more source

A Polynomial-time Algorithm for Outerplanar Diameter Improvement

open access: yes, 2014
The Outerplanar Diameter Improvement problem asks, given a graph $G$ and an integer $D$, whether it is possible to add edges to $G$ in a way that the resulting graph is outerplanar and has diameter at most $D$.
Cohen, Nathann   +6 more
core   +3 more sources

Reconstruction of maximal outerplanar graphs

open access: yesDiscrete 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   +2 more sources

On the Fiedler value of large planar graphs [PDF]

open access: yes, 2013
The Fiedler value $\lambda_2$, also known as algebraic connectivity, is the second smallest Laplacian eigenvalue of a graph. We study the maximum Fiedler value among all planar graphs $G$ with $n$ vertices, denoted by $\lambda_{2\max}$, and we show the ...
Alon   +25 more
core   +4 more sources

Face Sizes and the Connectivity of the Dual

open access: yesJournal of Graph Theory, Volume 110, Issue 4, Page 379-391, December 2025.
ABSTRACT For each c ≥ 1, we prove tight lower bounds on face sizes that must be present to allow 1‐ or 2‐cuts in simple duals of c‐connected maps. Using these bounds, we determine the smallest genus on which a c‐connected map can have a simple dual with a 2‐cut and give lower and some upper bounds for the smallest genus on which a c‐connected map can ...
Gunnar Brinkmann   +2 more
wiley   +1 more source

Dominating sets inducing large components in maximal outerplanar graphs [PDF]

open access: yesJournal of Graph Theory, 2017
AbstractFor a maximal outerplanar graph G of order n at least three, Matheson and Tarjan showed that G has domination number at most . Similarly, for a maximal outerplanar graph G of order n at least five, Dorfling, Hattingh, and Jonck showed, by a completely different approach, that G has total domination number at most unless G is isomorphic to one ...
José D. Alvarado   +2 more
openaire   +2 more sources

Recognizing Trees From Incomplete Decks

open access: yesJournal of Graph Theory, Volume 110, Issue 3, Page 322-336, November 2025.
ABSTRACT Given a graph G, the unlabeled subgraphs G − v are called the cards of G. The deck of G is the multiset { G − v : v ∈ V ( G ) }. Wendy Myrvold showed that a disconnected graph and a connected graph both on n vertices have at most ⌊ n 2 ⌋ + 1 cards in common and found (infinite) families of trees and disconnected forests for which this upper ...
Gabriëlle Zwaneveld
wiley   +1 more source

Home - About - Disclaimer - Privacy