The generator matrix

 1  0  1  1  1  1  1  1  1  0  1  1  1  1  2  1  1  1  1  2  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  2  0 2a 2a 2a  1  1  1  1  1  1  1  1  1  1  1  1  0  2 2a  1  1  1  1
 0  1  1  a a+1  0 2a+3 a+1  a  1 a+3  2 2a+3 a+2  1  2  1 a+2 a+3  1  0  2 2a+3 2a+1 2a+1 a+2 3a 3a a+1 a+3 2a 2a 3a+1 3a+1 2a+1  a 2a  1 3a 3a+1  1  1  1  1  1  0  2 2a 2a+3 2a+1  1  a a+2 3a a+1 a+3 3a+1  1  1  1 2a+2 2a+2 2a+2  0
 0  0 2a+2 2a  2  2  0 2a+2  0 2a 2a 2a+2 2a  2  2 2a  2 2a+2  0 2a+2 2a  2  2 2a+2  0 2a  0  2 2a 2a+2 2a+2  0  0  2 2a 2a+2  2  0 2a 2a+2  0  2 2a 2a+2  0 2a+2  0 2a 2a+2  2 2a  2  0 2a+2  0  2 2a 2a+2 2a  2 2a+2 2a  2  0

generates a code of length 64 over GR(16,4) who´s minimum homogenous weight is 188.

Homogenous weight enumerator: w(x)=1x^0+192x^188+723x^192+48x^196+48x^204+12x^208

The gray image is a code over GF(4) with n=256, k=5 and d=188.
This code was found by Heurico 1.16 in 0.031 seconds.