The generator matrix

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

generates a code of length 22 over GR(16,4) who´s minimum homogenous weight is 64.

Homogenous weight enumerator: w(x)=1x^0+45x^64+192x^66+15x^72+3x^88

The gray image is a code over GF(4) with n=88, k=4 and d=64.
This code was found by Heurico 1.16 in -1.01e-007 seconds.