The generator matrix

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

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+160x^57+330x^58+804x^59+588x^60+756x^61+1170x^62+846x^63+780x^64+768x^65+242x^66+48x^67+6x^68+16x^69+18x^70+8x^72+12x^73+6x^74+2x^78

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 0.0582 seconds.