The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 0  3  0  0  0  0  3  6  6  0  0  3  3  3  3  3  3  3  0  6  0  6  0  6  0  3  6  3  6  6  0  0  6  3  0  3  3  3  3  0  0  0  3  0  3  0  0  3  3  6  6  0  3  6  6  6  3  6  0  6  3  6  0  6  0  3  6  6  0  6  3  0
 0  0  3  0  0  3  6  0  6  0  3  3  6  6  0  3  0  3  3  3  3  0  0  6  6  3  3  6  0  6  0  3  3  0  6  6  0  3  0  6  6  6  3  6  6  0  0  6  3  0  3  3  3  0  6  0  6  6  6  3  3  3  6  6  6  0  6  3  3  0  0  0
 0  0  0  3  0  6  6  3  0  3  3  0  0  3  6  3  3  6  6  0  0  6  6  6  6  6  3  3  0  3  6  3  6  6  3  6  3  0  0  0  3  0  3  6  0  0  3  3  0  6  0  3  3  0  6  6  6  0  0  6  6  3  6  3  3  6  3  6  6  3  3  6
 0  0  0  0  3  6  6  6  6  6  0  6  0  0  6  6  0  3  0  0  6  6  3  6  3  6  0  6  0  0  6  6  3  0  0  0  6  0  3  3  6  6  3  0  3  6  3  3  3  0  6  3  0  3  0  3  3  3  0  6  0  6  6  6  3  3  3  0  3  0  3  0

generates a code of length 72 over Z9 who´s minimum homogenous weight is 138.

Homogenous weight enumerator: w(x)=1x^0+32x^138+54x^141+570x^144+38x^147+18x^150+12x^153+2x^156+2x^216

The gray image is a code over GF(3) with n=216, k=6 and d=138.
This code was found by Heurico 1.16 in 0.0856 seconds.