λ'-最优无三角图的最小边度充分条件The Minimum Edge Degree Conditions for Triangle-free Graphs Connectivity to be-optimal
刘爱霞,原军,吴红梅
摘要(Abstract)：
设S是连通图G的一个边割。若G-S不包含孤立点,则称S是G的一个限制边割。图G的最小限制边割的边数称为G的限制边连通度,记为λ'(G).如果图G的限制边连通度等于其最小度,则称图G是最优限制边连通的,简称λ'-最优的。设G是一个n阶的连通无三角图,且最小度δ(G)≥2.文章证明了,若最小边度ξ(G)≥(n/2-2 )(1+1/δ(G)-1),则G是λ'-最优的。并由此推出,若连通无三角图G的最小度δ(G)≥n/4+1,则G是λ'-最优的。最后给出例子说明这些结果给出的边界都是紧的。
关键词(KeyWords)： 无三角图;边连通度;限制边连通度
基金项目(Foundation): 数学天元基金(11126067);; 山西省自然科学基金(2012021001-2);; 太原科技大学博士启动金(20082014)
作者(Author): 刘爱霞,原军,吴红梅
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