The generator matrix

 1  0  1  1
 0  1 a^7*X+1  a

generates a code of length 4 over F9[X]/(X^2) who´s minimum homogenous weight is 24.

Homogenous weight enumerator: w(x)=1x^0+288x^24+32x^27+3888x^32+2304x^33+48x^36

The gray image is a linear code over GF(9) with n=36, k=4 and d=24.
This code was found by Heurico 1.16 in 0.000184 seconds.