The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  2  1
 0  2  0  6  0  6  4  6  0  6  4  2  4  2  4  2  0  6  6  0
 0  0  4  0  0  4  4  4  4  0  4  4  0  4  0  0  0  0  0  4
 0  0  0  4  4  4  4  0  4  0  0  0  4  4  0  4  0  0  4  4

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

Homogenous weight enumerator: w(x)=1x^0+8x^18+32x^19+46x^20+32x^21+7x^22+1x^24+1x^38

The gray image is a code over GF(2) with n=80, k=7 and d=36.
This code was found by Heurico 1.16 in 0.00191 seconds.