The generator matrix

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

generates a code of length 22 over GR(16,4) who´s minimum homogenous weight is 48.

Homogenous weight enumerator: w(x)=1x^0+63x^48+300x^52+384x^56+1332x^60+5229x^64+7656x^68+720x^72+468x^76+195x^80+36x^84

The gray image is a code over GF(4) with n=88, k=7 and d=48.
This code was found by Heurico 1.16 in 0.647 seconds.