The multicovering radii of a code are recently introduced natural generalizations of the covering radius measuring the smallest radius of balls around codewords that cover all m-tuples of vectors. In this paper we prove a new identity relating the multicovering radii of a code to a relativized notion of ordinary covering radius. This identity is used to prove new bounds on the multicovering rad...

A new quaternary linear code of length 19, codimension 5, and covering radius 2 is found in a computer search using tabu search, a local search heuristic. Starting from this code, which has some useful partitioning properties, di!erent lengthening constructions are applied to get an in"nite family of new, record-breaking quaternary codes of covering radius 2 and odd codimension. An algebraic co...