A Series of Separable Designs with Application to Pairwise Orthogonal Latin Squares

Abstract

We observe that a partition of PG (2, q 2 ) into Baer subplanes gives rise to certain separable pairwise balanced block designs (with λ =1) which in turn can be used to get more mutually orthogonal Latin squares of certain orders than previously known. As a side result we find an embedding of STS (19) in PG (2, 11), thus refuting a conjecture of M. Limbos.