The Conditions for Isomorphism of Two Graphs and Some Results on Four-Colorable Conjecture
Fugui Liu, Kai‐Sheng Lu · 2007
This paper gives a necessary condition for isomorphism of two graphs, and puts forward a new method about judging non-isomorphism of them. Besides, it presents a necessary and sufficient condition for isomorphism of two graphs by using a conclusion known in the reconstruction graph, and a new method for judging isomorphism of two graphs. It also proves the theorem; Let G be the planar graph of order p, then G is at most four colorable when 2 les p <11.