简单自反DTS(ν,λ)的存在谱

The Spectrum of Simple Self-Converse DTS(ν,λ)

一个Directed三元系DTS(ν,λ)=(X,B)是自反的,如果它与它的逆(X,B-1)同构,其中B-1={(z,y,x);(x,y,z)∈B}.继已给出SCDTS(ν,λ)的存在谱之后,又给出简单SCDTS(ν,λ)的存在谱.

A directed triple system DTS(ν,λ) = (X,B) is called self-converse if it and its converse (X,B-1) are isomorphic, where B-1= {(z,y,x); (x,y,z)∈B}. In this paper, the existence spectrum of simple self-converse DTS(ν,λ) is given, which is λν;(ν-1)≡0 (mod 3),λ≤3(ν-2) and (ν,λ)≠(6,l).