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

generates a code of length 47 over GR(16,4) who´s minimum homogenous weight is 136.

Homogenous weight enumerator: w(x)=1x^0+105x^136+84x^140+768x^141+15x^144+39x^152+9x^156+3x^188

The gray image is a code over GF(4) with n=188, k=5 and d=136.
This code was found by Heurico 1.16 in 0.031 seconds.