The generator matrix

 1  0  0  1  1  1  1  1  1  1 (a+1)X  1  1  1  1  1 aX  1  1  1  0  1  1  1  1  1  1  1 aX  1  0  1  1  1  1  X  1  1  1  X  1  1 (a+1)X  1  1  1  1
 0  1  0  0  X aX  1 (a+1)X+a  1 (a+1)X+1  1 (a+1)X+1 (a+1)X+a+1 X+a+1 aX+a (a+1)X+a+1  1 X+a a+1 X+a  1 (a+1)X+a X+a+1 (a+1)X+a+1  X aX+1 aX  0  1 aX  X (a+1)X (a+1)X+1  1  a  1  a (a+1)X  a aX  X  1  1 aX+a (a+1)X+a  a X+a+1
 0  0  1  1 (a+1)X+a (a+1)X+a+1 X+1 aX+1 a+1  a X+1  0 (a+1)X X+a+1 X+a+1  a aX+a+1 (a+1)X+a X+1 (a+1)X X+a (a+1)X+1 aX+a+1  1 X+a+1 X+a X+a aX+1  0  X  1 (a+1)X+1 aX aX+1 (a+1)X+1 aX+a+1 aX (a+1)X+a aX+a+1  1 aX+1 X+a aX  a (a+1)X+a  0 aX+a
 0  0  0 (a+1)X  0  0 (a+1)X (a+1)X  0  0  0  X aX aX (a+1)X  X  0 aX  X  X aX aX (a+1)X  0  X aX  X  X aX (a+1)X aX  0 aX  0  X  X (a+1)X (a+1)X  X (a+1)X aX (a+1)X  X aX  X aX aX

generates a code of length 47 over F4[X,sigma]/(X^2) who´s minimum homogenous weight is 131.

Homogenous weight enumerator: w(x)=1x^0+984x^131+540x^132+2376x^135+861x^136+3144x^139+888x^140+2340x^143+942x^144+2316x^147+570x^148+996x^151+273x^152+132x^155+15x^156+3x^160+3x^172

The gray image is a linear code over GF(4) with n=188, k=7 and d=131.
This code was found by Heurico 1.16 in 4.42 seconds.