The generator matrix

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

generates a code of length 28 over GR(16,4) who´s minimum homogenous weight is 64.

Homogenous weight enumerator: w(x)=1x^0+72x^64+267x^68+417x^72+993x^76+3159x^80+5772x^84+4521x^88+546x^92+384x^96+189x^100+54x^104+9x^108

The gray image is a code over GF(4) with n=112, k=7 and d=64.
This code was found by Heurico 1.16 in 0.944 seconds.