Results 61 to 70 of about 850,474 (224)
A Polynomial-time Algorithm for Outerplanar Diameter Improvement
, 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
Labeling Schemes for Bounded Degree Graphs [PDF]
, 2014 We investigate adjacency labeling schemes for graphs of bounded degree $\Delta = O(1)$. In particular, we present an optimal (up to an additive constant) $\log n + O(1)$ adjacency labeling scheme for bounded degree trees.
A. Korman +11 more
core +1 more source
Star Coloring Outerplanar Bipartite Graphs
Discussiones Mathematicae Graph Theory, 2019 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
On edge-intersection graphs of k-bend paths in grids [PDF]
Discrete Mathematics & Theoretical Computer Science, 2010 Edge-intersection graphs of paths in grids are graphs that can be represented such that vertices are paths in a grid and edges between vertices of the graph exist whenever two grid paths share a grid edge. This type of graphs is motivated by applications
Therese Biedl, Michal Stern
doaj +1 more source
Characterizations of outerplanar graphs
Discrete Mathematics, 1979 AbstractThe paper presents several characterizations of outerplanar graphs, some of them are counterparts of the well-known characterizations of planar graphs and the other provide very efficient tools for outerplanarity testing, coding (i.e. isomorphism testing), and counting such graphs.
openaire +2 more sources
On Vertices Enforcing a Hamiltonian Cycle
Discussiones Mathematicae Graph Theory, 2013 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
Strong Oriented Chromatic Number of Planar Graphs without Short Cycles [PDF]
Discrete Mathematics & Theoretical Computer Science, 2008 Let M be an additive abelian group. An M-strong-oriented coloring of an oriented graph G is a mapping f from V(G) to M such that f(u) j(v) whenever uv is an arc in G and f(v)−f(u) −(f(t)−f(z)) whenever uv and zt are two arcs in G.
Mickael Montassier +2 more
doaj +1 more source
On the colorings of outerplanar graphs
Discrete Mathematics, 1995 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire +2 more sources
Face Sizes and the Connectivity of the Dual
Journal of Graph Theory, EarlyView.ABSTRACT For each c≥1 $c\ge 1$, we prove tight lower bounds on face sizes that must be present to allow 1‐ or 2‐cuts in simple duals of c $c$‐connected maps. Using these bounds, we determine the smallest genus on which a c $c$‐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 $c ...
Gunnar Brinkmann +2 more
wiley +1 more source
Discrete Mathematics & Theoretical Computer Science, 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 cross.
Vida Dujmović +2 more
doaj +3 more sources