The generator matrix

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

generates a code of length 20 over Z4[X]/(X^3+2,2X) who´s minimum homogenous weight is 18.

Homogenous weight enumerator: w(x)=1x^0+14x^18+50x^19+111x^20+76x^21+1x^22+2x^23+1x^34

The gray image is a code over GF(2) with n=160, k=8 and d=72.
This code was found by Heurico 1.16 in 3.62e-008 seconds.