The generator matrix

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

generates a code of length 50 over GR(16,4) who´s minimum homogenous weight is 143.

Homogenous weight enumerator: w(x)=1x^0+540x^143+270x^144+1152x^147+375x^148+528x^151+96x^152+384x^155+156x^156+324x^159+102x^160+144x^163+21x^164+3x^176

The gray image is a code over GF(4) with n=200, k=6 and d=143.
This code was found by Heurico 1.16 in 0.063 seconds.