The generator matrix

 1  1  1  1  1  1  1  1  1  X  1  X  X  0 X^2  1  1  1
 0  X  0  0  0  X X^2+X  X  0  0 X^2 X^2  X  X  X X^2+X  0  0
 0  0  X  0  X  X X^2+X  0  0 X^2  X X^2+X  X  0 X^2 X^2+X  0 X^2
 0  0  0  X  X  0 X^2+X  X X^2  X  0  X  0 X^2  X X^2+X  0 X^2
 0  0  0  0 X^2  0  0  0 X^2 X^2 X^2  0  0  0  0 X^2 X^2  0
 0  0  0  0  0 X^2  0 X^2  0 X^2  0 X^2 X^2  0  0 X^2  0  0
 0  0  0  0  0  0 X^2 X^2 X^2  0 X^2  0 X^2 X^2  0  0  0 X^2

generates a code of length 18 over Z2[X]/(X^3) who´s minimum homogenous weight is 12.

Homogenous weight enumerator: w(x)=1x^0+66x^12+72x^13+161x^14+240x^15+457x^16+696x^17+684x^18+736x^19+452x^20+248x^21+166x^22+48x^23+46x^24+8x^25+12x^26+2x^28+1x^30

The gray image is a linear code over GF(2) with n=72, k=12 and d=24.
This code was found by Heurico 1.16 in 0.145 seconds.