The generator matrix

 1  0  0  1  1  1  2  4  1  1  1  1  1  1  1  2  1  6  2  1
 0  1  0  1  4  5  1  1  1  4  2  7  6  0  3  1  2  1  4  6
 0  0  1  4  1  5  5  5  2  3  0  7  6  6  2  3  4  4  2  3

generates a code of length 20 over Z8 who´s minimum homogenous weight is 18.

Homogenous weight enumerator: w(x)=1x^0+158x^18+96x^19+82x^20+72x^21+40x^22+16x^23+21x^24+8x^25+18x^26

The gray image is a code over GF(2) with n=80, k=9 and d=36.
This code was found by Heurico 1.11 in 104 seconds.