The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  X
 0  X  0  0  X  X  0  X 2X 4X 3X 4X 4X 3X  0  X 4X  X 3X 4X  X
 0  0  X  0 3X 2X  X 4X  0  X  X  X  0  X 2X  0 4X 3X 4X 3X  X
 0  0  0  X 3X  X 4X 3X 3X 3X  0  X 3X 4X  X  X 4X 2X  0 4X 4X

generates a code of length 21 over Z5[X]/(X^2) who´s minimum homogenous weight is 75.

Homogenous weight enumerator: w(x)=1x^0+152x^75+680x^80+2124x^85+64x^90+24x^95+56x^100+24x^105

The gray image is a linear code over GF(5) with n=105, k=5 and d=75.
This code was found by Heurico 1.16 in 0.447 seconds.