973 search results - page 5 / 195 » New Bounds on Crossing Numbers |
ESA
2008
Springer
13 years 9 months ago
2008
Springer
The crossing number problem is to find the smallest number of edge crossings necessary when drawing a graph into the plane. Eventhough the problem is NP-hard, we are interested in ...
COMBINATORICS
2002
13 years 7 months ago
2002
We give two lower bound formulas for multicolored Ramsey numbers. These formulas improve the bounds for several small multicolored Ramsey numbers.
ALGORITHMICA
2011
13 years 2 months ago
2011
We show that computing the crossing number and the odd crossing number of a graph with a given rotation system is NP-complete. As a consequence we can show that many of the well-k...
GD
2007
Springer
14 years 1 months ago
2007
Springer
We show that computing the crossing number of a graph with a given rotation system is NP-complete. This result leads to a new and much simpler proof of Hlinˇen´y’s result, tha...
DM
2007
13 years 7 months ago
2007
In this paper, we obtain some new results R(5, 12) 848, R(5, 14) 1461, etc., and we obtain new upper bound formulas for Ramsey numbers with parameters. © 2006 Published by Elsevi...