The generator matrix

 1  0  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  X  1  1
 0  1 a^6*X+1  a a^6*X+a^2 a^3 a^6*X+a^4 a^5 a^6*X+a^6  X a^5*X+1 X+a a^5*X+a^2 X+a^3 a^5*X+a^4 X+a^5 a^5*X+a^6  1 a*X a^4*X+1

generates a code of length 20 over F8[X]/(X^2) who´s minimum homogenous weight is 134.

Homogenous weight enumerator: w(x)=1x^0+784x^134+336x^135+14x^136+2352x^142+560x^143+49x^144

The gray image is a linear code over GF(8) with n=160, k=4 and d=134.
This code was found by Heurico 1.16 in 0.00172 seconds.