λK_v∪λDK_v的三角形分解

On Triangle-decomposition of λK_v∪λDK_v

运用组合设计中的PBD方法、差分法等,结合一些已知的PBD存在结果及一些小阶数三角形分解的巧妙构造,给出了3类mixed三角形分解Ti(v,λ)(i=1,2,3)存在的充分必要条件.

By using the methods of PBD and difference,the necessary and sufficient conditions for the existence of T_i(v,λ)(i=1,2,3) are obtained.In the construction some results of PBD as well as some triangle-decomposition of certain orders are used.