【摘要】 给出某些4 连通图中圈上的可收缩边和可去边的分布情况,得到如下结果:最小度至少为4或围长至少为5的4 连通图,其任一圈上至少有两条可去边;对4 连通图中的某些最长圈上至少有两条可收缩边.更多还原

【Abstract】 In this paper we show that in a 4connected graph G with minimum degree at least four or girth at least five, any cycle C of G contains at least two removable edges. Moreover, any longest cycle C of a 4connected graph G contains at least two contractible edges of G whenever the degree of each vertex in C is at least five or there is no 3cycle in the induced subgraphin G.更多还原