Papers Published
Abstract:
We obtain a new necessary condition for the existence of a 2-(υ, k, λ) design where the block intersection sizes s1,s2,...,sn satisfy s1≡s2≡...≡sn≡s( mod 2). This condition eliminates quasi-symmetric 2-(20, 10, 18) and 2-(60, 30, 58) designs. Quasi-symmetric 2- (20, 8, 14) designs are eliminated by an ad hoc coding theoretic argument. © 1990.