The generator matrix

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

generates a code of length 75 over GR(16,4) who´s minimum homogenous weight is 213.

Homogenous weight enumerator: w(x)=1x^0+444x^213+696x^214+252x^215+39x^216+1164x^217+1212x^218+600x^219+63x^220+1428x^221+1464x^222+408x^223+45x^224+1416x^225+1332x^226+372x^227+42x^228+1056x^229+924x^230+336x^231+27x^232+564x^233+684x^234+180x^235+15x^236+492x^237+456x^238+108x^239+15x^240+312x^241+132x^242+48x^243+36x^245+12x^246+6x^248+3x^256

The gray image is a code over GF(4) with n=300, k=7 and d=213.
This code was found by Heurico 1.16 in 1.3 seconds.