16 Giugno, 2017 15:30 in punto

Sezione di Geometria, Algebra e loro applicazioni

Designs with speci?c automorphism group

Yanxun Chang, Department of Mathematics, Beijing Jiaotong University, P. R. China

Aula seminari III piano

Let v, k and t be positive integers such that v > k > t. A Steiner t-wise balanced design (brie?y S(t,k,v)) is a pair (X,B), where X is a set of v points and B is a set of k-subsets of X (called blocks) such that every t-subset of X is contained in a unique block. An automorphism group of a S(t,k,v) (X,B) is a permutation group on X leaving B invariant. In this talk, we consider Steiner t-wise balanced design with speci?c automorphism. Some direct and recursive constructions on this topics are summarized.