A symmetric BIBD with trivial automorphism group
Iff combinatorial conditions for a BIBD(r-1,b,r,\(\lambda\)-1,\(\lambda)\) with \(vr=b(\lambda +1)\) to be embeddable as a derived design in a SBIBD are given. Using the above conditions a BIBD is completed to 13 nonisomorphic SBIBD(36,15,6); several of them have no proper automorphisms.
scientific article; zbMATH DE number 3918371