Mass formulas for self-dual codes over Z/sub 4/ and F/sub q/+uF/sub q/ rings

We give a mass formula for quaternary self-dual and type II codes and for self-dual codes over F/sub q/+uF/sub q/ rings. We define type II codes and compute the number of distinct type II codes. We also give formulas for the number of doubly even binary codes, necessary to compute N/sub d/(n), the number of distinct codes of length n, for any dimension n, and conclude that the classification of quaternary self-dual codes could be reasonably extended to length 14.