The generator matrix

 1  1  1  1  1  1  1  1
 0  5  0  0  5  5  0  5
 0  0  5  0 15 10  5 15
 0  0  0  5 15  5 20 15

generates a code of length 8 over Z25 who´s minimum homogenous weight is 20.

Homogenous weight enumerator: w(x)=1x^0+68x^20+72x^25+148x^30+2500x^32+208x^35+128x^40

The gray image is a code over GF(5) with n=40, k=5 and d=20.
This code was found by Heurico 1.16 in 0.0018 seconds.