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

generates a code of length 51 over GR(16,4) who´s minimum homogenous weight is 144.

Homogenous weight enumerator: w(x)=1x^0+24x^144+57x^148+87x^152+768x^153+39x^156+21x^160+15x^164+3x^168+6x^172+3x^204

The gray image is a code over GF(4) with n=204, k=5 and d=144.
This code was found by Heurico 1.16 in 0.031 seconds.