The generator matrix

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

generates a code of length 64 over GR(16,4) who´s minimum homogenous weight is 184.

Homogenous weight enumerator: w(x)=1x^0+339x^184+180x^185+204x^186+336x^187+657x^188+192x^189+48x^190+132x^191+507x^192+216x^193+12x^194+168x^195+276x^196+84x^197+12x^198+60x^199+168x^200+36x^201+84x^202+48x^203+147x^204+36x^205+12x^206+24x^207+78x^208+24x^209+12x^210+3x^216

The gray image is a code over GF(4) with n=256, k=6 and d=184.
This code was found by Heurico 1.16 in 0.094 seconds.