Conditions for the Parameters of the Block Graph of Quasi-Symmetric Designs

[摘要] A quasi-symmetric design (QSD) is a 2-$(v,k,\lambda)$ design with intersection numbers $x$ and $y$ with $x< y$. The block graph of such a design is formed on its blocks with two distinct blocks being adjacent if they intersect in $y$ points. It is well

[学科分类] 离散数学和组合数学

[关键词] Quasi-symmetric design;Strongly regular graph;Block Graph