540 search results - page 3 / 108 » New bounds on the edge number of a k-map graph |
JCT
2007
13 years 7 months ago
2007
A topological graph is quasi-planar, if it does not contain three pairwise crossing edges. Agarwal et al. [2] proved that these graphs have a linear number of edges. We give a sim...
ALGORITHMICA
2011
13 years 2 months ago
2011
A nonplanar graph G is near-planar if it contains an edge e such that G−e is planar. The problem of determining the crossing number of a near-planar graph is exhibited from diffe...
CORR
2011
Springer
13 years 2 months ago
2011
Springer
Given a graph G, an obstacle representation of G is a set of points in the plane representing the vertices of G, together with a set of connected obstacles such that two vertices ...
DM
2008
13 years 7 months ago
2008
We prove that a K4-free graph G of order n, size m and maximum degree at most three has an independent set of cardinality at least 1 7 (4n - m - - tr) where counts the number of c...
DM
2000
13 years 7 months ago
2000
The Zarankiewicz number z(s, m) is the maximum number of edges in a subgraph of K(s, s) that does not contain K(m, m) as a subgraph. The bipartite Ramsey number b(m, n) is the lea...