186 search results - page 28 / 38 » Exceptional planar polynomials |
JGT
2008
13 years 7 months ago
2008
A homomorphism from an oriented graph G to an oriented graph H is a mapping from the set of vertices of G to the set of vertices of H such that ----(u)(v) is an arc in H whenever...
JGT
2007
13 years 7 months ago
2007
It is known that for every integer k ≥ 4, each k-map graph with n vertices has at most kn − 2k edges. Previously, it was open whether this bound is tight or not. We show that ...
DM
2011
13 years 2 months ago
2011
Let G be the set of finite graphs whose vertices belong to some fixed countable set, and let ≡ be an equivalence relation on G. By the strengthening of ≡ we mean an equivalen...
ALT
2007
Springer
14 years 4 months ago
2007
Springer
Algorithms based on upper-confidence bounds for balancing exploration and exploitation are gaining popularity since they are easy to implement, efficient and effective. In this p...
LATA
2009
Springer
14 years 2 months ago
2009
Springer
Abstract. Gene trees are leaf-labeled trees inferred from molecular sequences. Due to duplication events arising in genome evolution, gene trees usually have multiple copies of som...