六点有向θ图设计

The Graph Design of Directed Graphs of C_6^(1),C_6^(2)

设Kv是一个v点的有向完全图,G是一个简单有向图。Kv的一个G-设计(记为(v,G,λ)-GD)是指一个二元组(X,B),其中X为kv的点集,B为Kv的一些子图(也称为区组)构成的集合。任一子图(区组)与G同构,且Kv的任意两个不同点组成的有向边恰在B的一个区组中出现。本文研究了不同构的六点有向θ图设计的存在性问题。

Let Kv be a complete directed graph with v vertices, G be a simple directed subgraph. A G- design of Ko,denoted by （v,G,λ）-GD, is a pair （X, B）, where X is the vertices set of Kv,and B is the collection of Kv subgraphs （blocks） of Kv, such that each block is isomorphic to G, and any edge in K, occurs in exactly one subgraph. In this article, the author studies the existence of graph design of non-isomorphic simple directed graphs of C6^（1）,C6^（2）.