Sciweavers

73 search results - page 8 / 15
» jct 2007
Sort
View
JCT
2007
103views more  JCT 2007»
13 years 8 months ago
Geometric drawings of Kn with few crossings
We give a new upper bound for the rectilinear crossing number cr(n) of the complete geometric graph Kn. We prove that cr(n) ≤ 0.380559 ¡n 4 ¢ + Θ(n3 ) by means of a new const...
Bernardo M. Ábrego, Silvia Fernández...
JCT
2007
149views more  JCT 2007»
13 years 8 months ago
Weighted forms of Euler's theorem
In answer to a question of Andrews about finding combinatorial proofs of two identities in Ramanujan’s “lost” notebook, we obtain weighted forms of Euler’s theorem on part...
William Y. C. Chen, Kathy Q. Ji
JCT
2007
119views more  JCT 2007»
13 years 8 months ago
Cliques and the spectral radius
We prove a number of relations between the number of cliques of a graph G and the largest eigenvalue (G) of its adjacency matrix. In particular, writing ks (G) for the number of s...
Béla Bollobás, Vladimir Nikiforov
JCT
2007
108views more  JCT 2007»
13 years 8 months ago
The cover time of the preferential attachment graph
The preferential attachment graph Gm(n) is a random graph formed by adding a new vertex at each time step, with m edges which point to vertices selected at random with probability...
Colin Cooper, Alan M. Frieze
JCT
2007
96views more  JCT 2007»
13 years 8 months ago
Induced subgraphs of Ramsey graphs with many distinct degrees
An induced subgraph is called homogeneous if it is either a clique or an independent set. Let hom(G) denote the size of the largest homogeneous subgraph of a graph G. In this shor...
Boris Bukh, Benny Sudakov