Guichard-Combinatorics-Graph-Theory · Problem 5.10.1
Graph Theory
Mathematics — Probability · coloring-planar-graphs
Problem
Show K3,3 is not planar. (Prove a lemma like lemma 5.10.3 for bipartite graphs, then do something like the proof of theorem 5.10.4.) What is the chromatic number of K3,3?