关于区组大小为5的准可分解BIBD的存在性

On the Existence of Almost Resolvable BIBDs with Block size Five

设(X,A)是一个(v,k,λ)—BIBD.若A能划分成一些准平行类的并,则(X,A)称为准可分解的,且记作(v,k,λ)—ARBIBD.我们证明,当v≥15926时,存在(v,5,λ)—ARBIBD的必要条件也是充分的.

Let(X, A ) be a ( v, k, λ ) - BIBD. ( X, A ) is called almost eso lvable and denoted by ( v, k,λ)-ARBIBD. if A can be p rtitioned into almost parallel classes.We prove in this paper that when v 1 9 6, the necessary condition for the existence of almost resolvable BIBDs with block size five is also sufficient