Maximum bipartite subgraphs of cubic triangle-free planar graphs

摘要

Thomassen recently proved, using the Tutte cycle technique, that if G is a 3-connected cubic triangle-free planar graph then G contains a bipartite subgraph with at least 29|V(G)/24—7/6 edges, improving thepreviously known lower bound 6|V(G)|/5. We extend Thomassen's technique and further improve this lower bound to 39|V(G)|/32-9/16