The generator matrix

 1  1  1  1  1  1
 0  X  0  0  0  X
 0  0  X  0  0 2X
 0  0  0  X  0 2X
 0  0  0  0  X  X

generates a code of length 6 over Z3[X]/(X^2) who´s minimum homogenous weight is 6.

Homogenous weight enumerator: w(x)=1x^0+30x^6+40x^9+576x^12+60x^15+22x^18

The gray image is a linear code over GF(3) with n=18, k=6 and d=6.
This code was found by Heurico 1.16 in 0.000273 seconds.