The generator matrix

 1  0  1  1  1  1  1  1  3  1  1  1  1 2X+3  1  1  1 X+3  1  0
 0  1  1  8  3  2  0 2X+1  1  7 X+3  1 X+8  1 2X+2 X+7 X+7  1  7  X
 0  0 2X  6 X+6 X+3 2X+6  X  X 2X+3 2X+6 X+3 X+6  X X+6 2X+6 2X  0  3 X+3

generates a code of length 20 over Z9[X]/(X^2+3,3X) who´s minimum homogenous weight is 36.

Homogenous weight enumerator: w(x)=1x^0+540x^36+216x^37+954x^38+1158x^39+540x^40+1332x^41+1332x^42+216x^43+144x^44+114x^45+12x^48+2x^54

The gray image is a code over GF(3) with n=180, k=8 and d=108.
This code was found by Heurico 1.16 in 0.0688 seconds.