λ_4-最优图的一个充分条件

A Sufficient Condition for Graphs to be λ_4-Optimal

文章给出了λ4-最优图的一个充分条件.设G是阶为n≥11的λ4-连通图,若对G中任意一对不相邻顶点u,v,有|N(u)∩N(v)|≥6且G|N(u)∩N(v)|至少包含16条边,则G是λ4-最优的.

A sufficient condition for a graph to be λ4-optimal has been given,Let G be a λ4-connected graph of order n≥11.If ｜N（u）∩N（v）｜≥6 for all pairs u,v of nonadjacent vertices,and G[N（u）∩N（v）] contains at least 16 edges,then G is λ4-optimal.