The generator matrix

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

generates a code of length 46 over GR(16,4) who´s minimum homogenous weight is 123.

Homogenous weight enumerator: w(x)=1x^0+336x^123+474x^124+288x^125+408x^126+1716x^127+1557x^128+828x^129+1224x^130+3480x^131+2739x^132+1788x^133+1452x^134+5772x^135+4557x^136+2040x^137+2448x^138+7296x^139+5013x^140+2232x^141+2448x^142+6060x^143+3789x^144+1740x^145+1032x^146+2712x^147+1068x^148+300x^149+204x^150+276x^151+153x^152+45x^156+36x^160+15x^164+6x^172+3x^176

The gray image is a code over GF(4) with n=184, k=8 and d=123.
This code was found by Heurico 1.16 in 13.4 seconds.