Ks,t Minors in (s+t)- Chromatic Graphs, II
Let denote the graph obtained from the complete graph by deleting the edges of some -subgraph. The author proved earlier that for each fixed s and , every graph with chromatic number has a minor. This confirmed a partial case of the corresponding conjecture by Woodall and Seymour. In this paper, we show that the statement holds already for much smaller t, namely, for .
graph coloring graph minors complete bipartite graphs 05c15 05c83