最大度为6的平面图为第一类的一个新充分条件

A new sufficient condition for a planar graph of maximum degree six to be Class 1

本文证明了:若一个平面图G不含带弦的6-圈,则G是第一类的.这部分地证实了Vizing的关于平面图边染色的一个猜想.

We prove that every planar graph G with △ = 6 is of Class 1 if it does not contain a 6-cycle with a chord,where △ denotes the maximum degree of G.This provides a positive evidence to Vizing＇s conjecture on edge coloring of planar graphs.