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

generates a code of length 78 over GR(64,4) who´s minimum homogenous weight is 536.

Homogenous weight enumerator: w(x)=1x^0+938x^536+1246x^544+1806x^552+98x^560+7x^576

The gray image is a code over GF(8) with n=624, k=4 and d=536.
This code was found by Heurico 1.16 in 0.078 seconds.