Topological invariants of 2-designs arising from difference families
The authors study \(2\text{-}(v,3, \lambda)\)-designs \(D\) on an abelian group of odd order s.t. translations by group elements are automorphisms of \(D\), to get a list of invariants of topological character useful also to give upper bounds on the order of the automorphism group of \(D\) and even (in certain cases) to find the exact structure of such group. Some methods of constructing designs are presented: they give many different designs which can be distinguished using the topological invariants above. Many examples and some open problems are given. Unfortunately main ideas and developments are too long to be reproduced here.
scientific article; zbMATH DE number 3855118