双圈与双圈拟阵的连通性

Connectivity of Bicircular and Bicircular Matroid

对双圈G与双圈拟阵B(G)的连通性进行了研究,比较了它们的连通度。在讨论双圈拟阵的秩函数r(X)和用用极小顶割集AG(G[X])表示了连通函数k(X)的基础上,由主要引理"M是Tutten-连通的,且(X,E-X)是M的一个满足o(X)=min{o(X′):(X′,E-X′)是M的一个Tutten-分离划分},则G[X],G[E-X]都是连通的",推出如下结果:(1)用统一方法证明"B(G)是Tutten-连通的G是n-双圈连通的"等三个命题;(2)比较了连通度,给出双圈与双圈拟阵各种连通性的图形交换.

The connectivity between Bicircular Gand Bicircular Matroid B（G） is compared. Express the connectivity function k（X） by top-Cut Set AG（G（X） ）. On the foundation of the rank function r（X） and connectivity functuion k（X）, of the main lemma and gain the some main results as follow are makd use of： （1） Prove thethree equivalent propositions as ＂B（G） is Tutten-separation ＂ and ＂Gis n-Tutten-separation＂ is a equivalent proposition. （2） compare the connectivity and give a variety of graphics interchange between Bicircular and Bicircuiar Matroid.