【摘要】 得到Δ free图的最长路和最长圈的下界为 2δ + 2 ,以及存在Hamilton圈的一个充分条件 :δ≥max{p3,α},δ是图G的顶点的最小度 ,α是G的独立数p =|V(G) |≥ 1 5 .更多还原

【Abstract】 Cycles and paths are basic concepts in graphs.Let δ be the minimum degree of the all vertices in a graph G.α is the cardinal number of the largest independent set in graph C.A lower bound of the longest path or cycle, 2δ +2 and efficient condition of Hamilton cycle, δ ≥max{ p/3-1,α }.are derived in a Δ free graph,where p=｜V(G)｜≥15.更多还原