设G=(V1,V2;E)是一个二分图,其顶点数目满足|V1|=|V2|=n≥(k+1)s+1,s和k是满足s≥3并且k≥1的两个正整数.定义σ1,1为图G的属于不同分划中的不相邻顶点的最小度和,证明了如果σ1,1(G)≥2F(1-1/s)n]+2,则G有一个2-因子包含至少k个圈,使得每个圈的长至少为2s.
Let G = ( V1, V2 ; E) be a bipartite graph with |V1 | = | V2 | = n 〉 ( k + 1 ) s + 1, s and k are two integers with s ≥ 3 and k≥ 1. Define σ1,1 , as the minimum degree of nonadjacent vertices of G. It is proved that if σ1,1 (G) ≥2[(1 - 1/s) n ] + 2, then G contains a 2, factor with at least k cycles, such that the length of every cycle is at least 2s.