Title
Unavoidable subgraphs of colored graphs
Abstract
A natural generalization of graph Ramsey theory is the study of unavoidable sub-graphs in large colored graphs. In this paper, we find a minimal family of unavoidable graphs in two-edge-colored graphs. Namely, for a positive even integer k, let S\"k be the family of two-edge-colored graphs on k vertices such that one of the colors forms either two disjoint K\"k\"/\"2's or simply one K\"k\"/\"2. Bollobas conjectured that for all k and @e0, there exists an n(k,@e) such that if n=n(k,@e) then every two-edge-coloring of K\"n, in which the density of each color is at least @e, contains a member of this family. We solve this conjecture and present a series of results bounding n(k,@e) for different ranges of @e. In particular, if @e is sufficiently close to 12, the gap between our upper and lower bounds for n(k,@e) is smaller than those for the classical Ramsey number R(k,k).
Year
DOI
Venue
2008
10.1016/j.disc.2007.08.102
Discrete Mathematics
Keywords
Field
DocType
unavoidable structures,05c55,ramsey theory,edge coloring,upper and lower bounds,ramsey number
Graph theory,Integer,Ramsey theory,Discrete mathematics,Combinatorics,Disjoint sets,Vertex (geometry),Upper and lower bounds,Ramsey's theorem,Conjecture,Mathematics
Journal
Volume
Issue
ISSN
308
19
Discrete Mathematics
Citations 
PageRank 
References 
3
0.51
3
Authors
2
Name
Order
Citations
PageRank
Jonathan Cutler130.51
Balázs Montágh230.51