The generator matrix

 1  0  1  1  1  1  1 X+6  1  1  1 2X  1  1  0  1  1  1  1  1  1  1  1 X+6  1  1  1  0  3  1  1
 0  1 2X+7  8 X+6 X+1 X+5  1 2X 2X+8  7  1 X+1 X+6  1  8 X+5 2X+8  0 2X 2X+7  8  7  1  2 2X+7 2X+4  1  1 2X 2X+3
 0  0  6  0  6  3  3  3  0  0  3  0  3  6  0  6  3  3  0  6  6  0  6  3  3  3  0  6  3  0  6
 0  0  0  3  6  6  3  0  3  6  0  6  3  0  3  6  0  6  6  3  6  0  3  3  6  0  6  6  6  0  0

generates a code of length 31 over Z9[X]/(X^2+6,3X) who´s minimum homogenous weight is 57.

Homogenous weight enumerator: w(x)=1x^0+336x^57+534x^58+680x^60+1644x^61+1212x^63+1620x^64+418x^66+60x^67+22x^69+30x^70+2x^72+2x^84

The gray image is a code over GF(3) with n=279, k=8 and d=171.
This code was found by Heurico 1.16 in 1.16 seconds.