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

generates a code of length 29 over GR(16,4) who´s minimum homogenous weight is 76.

Homogenous weight enumerator: w(x)=1x^0+225x^76+126x^80+183x^84+3072x^87+48x^88+234x^92+57x^96+102x^100+24x^104+21x^108+3x^116

The gray image is a code over GF(4) with n=116, k=6 and d=76.
This code was found by Heurico 1.16 in 9.35 seconds.