摘要
在Sylvester-Gallai定理与Erdos-de Bruijn定理的基础上,对点线系统的分类与计数问题进行研究,给出了点线系统中线的数量的计算公式与取值范围,并给出点线系统的若干推广,同时对广义点线系统与区组设计之间的关系进行了讨论,对区组设计的一些基本定理进行了推广.
Base on two famous theorems in combinatorial geometry,the Sylvester-Gallai theorem and the Erdos-de Bruijn theorem,the classification and enumeration problems on point-line systems are investigated.The formulae and ranges of the numbers of lines in point-line systems are given.Moreover,some generations of point-line systems are given.The relations between generalized point-line systems and block designs are discussed.As consequences,some basic theorems on block designs are generalized.
引文
[1]Aigner,M.,Ziegler,G.M.数学天书中的证明:第3版[M].冯荣权,宋春伟,宗传明,译.北京:高等教育出版社,2009:21-33.
[2]De Bruijn-Erdos theorem(incidence geometry)[EB/OL].http://en.wikipedia.org/wiki/De_Bruijn%E2%80%93Erd%C5%91s_theorem_(incidence_geometry).
[3]卢开澄.卢华明.组合数学:第3版[M].北京:清华大学出版社,2002:45-62.