The University of Michigan Combinatorics Seminar
Fall 2001
September 7, 4:10-5:00, 3866 East Hall

Record-breaking codes

Harm Derksen

University of Michigan


Let A(n,d) be the largest cardinality of a binary code of length n with minimal distance d. Several lower and upper bounds are known, and a few will be discussed. I will explain a construction of some good codes which lead to record breaking lower bounds for A(n,d). These codes are based on additive number theory and are similar to constant weight codes constructed by Graham and Sloane.