星图S4的交叉数

摘要

研究网络拓扑结构图星图S4的交叉数问题.首先构造星图S4好的画法,得到了S4交叉数的上界,然后给出了S4交叉数下界的数学证明,最终得到S4的交叉数的精确值为8.同时给出了与其具有同构关系的图S4,3和图A4,3的交叉数.%The problem of the crossing number about network topological structure graph S4 is studied.Firstly,by constructing a good drawing of Star graph S4 ,an upper bound of the crossing number of S4 is obtained.Then,the lower bound of the crossing number of S4 is obtained by mathematical proof.Lastly,the conclusion is drawn that the exact value of the crossing number of S4 is 8.Meanwhile,the crossing numbers of graph S4,3 and graph A4,3 ,which are isomorphic to S4 ,are given.