Extremal Self-Dual Codes over Z6, Z8 and Z10
Thomas Aaron Gulliver, Masaaki Harada, Mariko Hagita · AKCE International Journal of Graphs and Combinatorics · 2005
In this paper, upper bounds on the minimum Euclidean weights of Type I codes over Z6 , and self-dual codes over Z8 and Z10 , are derived for modest lengths. The notion of extremality for Euclidean weights is also introduced. We construct new extremal self-dual codes over these rings. Most of these codes are obtained via the double circulant and quasitwisted constructions. New extremal odd unimodular lattices are obtained from some of these codes by Construction A.