Covering triples by quadruples: an asymptotic solution
Journal of Combinatorial Theory Series A
Subdesigns in Steiner quadruple systems
Journal of Combinatorial Theory Series A
Bounds on the sizes of constant weight covering codes
Designs, Codes and Cryptography
On group divisible covering designs
Discrete Mathematics
Handbook of Combinatorial Designs, Second Edition (Discrete Mathematics and Its Applications)
Handbook of Combinatorial Designs, Second Edition (Discrete Mathematics and Its Applications)
Hi-index | 0.00 |
Let K q (n, w, t, d) be the minimum size of a code over Z q of length n, constant weight w, such that every word with weight t is within Hamming distance d of at least one codeword. In this article, we determine K q (n, 4, 3, 1) for all n 驴 4, q = 3, 4 or q = 2 m + 1 with m 驴 2, leaving the only case (q, n) = (3, 5) in doubt. Our construction method is mainly based on the auxiliary designs, H-frames, which play a crucial role in the recursive constructions of group divisible 3-designs similar to that of candelabra systems in the constructions of 3-wise balanced designs. As an application of this approach, several new infinite classes of nonuniform group divisible 3-designs with block size four are also constructed.