关于哈密尔顿连通图的一个基本结果是Ore给出的:设G是n阶图,若对于任意两个不相邻顶点u和v,有d(u)+d(v)≥n+1,则G是哈密尔顿连通的.设G是一个图,对于任意U∈V(G),令N(U)=Uu∈uN(u),d(U)=|N(U)|,称d(U)是U的度.本文利用独立集的度和得到如下结果:设s和t是正整数,G是(2s+2t+1)-连通n阶图.若对于任两个强不交独立集S,T,|S|=s,|T|=t,有d(S)+d(T)≥n+1,则G是哈密尔顿连通的.同时也得到图的哈密尔顿性的其它相关结果. 两个独立集S和T称为强不交的,如果SUT也是独立集.
One of the fundamental results concerning hamiltonian-connected graphs is due to Ore: If G is a graph of order n≥ 3 such that d(u) +d(v)≥ n+ 1 for every pair of nonadjacent vertices u, v ∈ V(G), then G is hamiltonian-connected. Let G be a graph, for any U C↓_ V(G), let N(U) = Uu∈uN(u), d(U) -= |N(U)|. In this paper, we give the following result: Let s and t be two positive integers and G be a (2s + 2t + 1)-connected graph of order n. If d(S) + d(T) ≥ n + 1 for every two strongly disjoint independent sets S and T with |S| = s and |T| =- t, then G is hamiltonian-connected. Other related results are obtained too.