摘要
We state that the flag-transitive automorphism group of a 2-(v,5,λ)design D is primitive of affine type or almost simple type.W e also find that there are up to isomorphism 202-(v,5,λ)designs admitting flag-transitive automorphism groups with socle of a sporadic simple group.
基金
supported by the National Natural Science Foundation of China(Grant No.11871224).
