Supplementary difference sets and D-optimal designs for n == 2 mod 4

Supplementary difference sets 2{12n; k, r; λ} are used to construct D-optimal designs for n ≡ 2 mod 4, where k, r, λ are defined through n. A number of new designs is constructed. The D-optimal design for n ≡ 86 is constructed for the first time. For n ≡ 2 mod 4, n<100 and for the cases n = 22, 34, 58, 70, 74, 78, 90, 94, 98, the D-optimal designs still remain unknown.