典型群PSU(3,q^2)与2-(v,k,1)设计

CLASSICAL GROUPSPSU(3,q^2 ) AND2 - (v,k,1) DESIGNS

讨论自同构群是酉群 PSU(3 ,q2 ) (q=2 l)的区 -本原的 2 -(v,k,1 )设计 .首先证明了它必是点 -本原的 ,然后确定了这种类型的设计 ,即它只能为 2 -(q3+1 ,q+1 ,1 )

Let Dbe a2 -(v,k,1 ) design and G≤ Aut Dbe the automorphism group of D.In this paper,itis proved thatif G is block-primitive and G PSU(3 ,q2 ) (q=2 l) ,then it is also point-primitive.Moreover,the design of this type must be a Hermitian unital,i.e a 2 -(q3+1 ,q+1 ,1 ) design.