简单无向连通图的k阶幂图的指数集

The Exponent Set of the k-th Power Graph of Simple Undirected Connected Graph

设Ｇ为简单无向图，以Ｖ＝Ｖ（Ｇ）为顶点集，以Ｅ＝｛（ｕ，ｖ）｜ｄ（ｕ，ｖ）≤ｋ｝为边集的图称为Ｇ的ｋ阶幂图。ｎ阶简单无向连通图的ｋ（ｋ≥２）阶幂图的指数集。

Let G be a simple undirected graph,the k-th power of G,denoted by GK,is definedas the graph with venices set V= V(G)and edges set E={(u, v)|d(u,v)≤k}.The exponent setof the k-th(k≥2)power graph of simple undirected connected graph is ES(k,n)=