Abstract: | The problem of determining Aq(n,d), the maximum cardinality of a q-ary code of length n with minimum distance at least d, is considered in some cases where corresponding MDS codes do not exist. Slight improvements of the Singleton bound are given, including Aq(q+2,q)?q3-3 if q is odd, A5(7,5)?53-4 and A16(18,15)?184-4. |