A leads to idempotent pairwise orthogonal Latin squares of order with one common hole of order . ’s can also be used to construct perfect Mendelsohn designs and optimal optical orthogonal codes. For , the spectrum for has been determined. In this article, we investigate the existence of with and show that a always exists in for any prime power with the exception of and one possible exception of .
Keywords: vector; Orthogonal Latin square; Perfect Mendel- sohn designs, Cyclotomic class