The generator matrix

 1  0  0  0  0  0  1  1  1  0  1  2  2  2  0  1  1  1  1  2  1
 0  1  0  0  0  0  0  0  3  0  1  1  1  2  1  1  1  0  3  1  2
 0  0  1  0  0  0  0  3  1  1  1  0  2  1  0  2  2  2  1  1  2
 0  0  0  1  0  0  0  1  0  0  3  1  2  1  2  1  3  2  3  1  0
 0  0  0  0  1  0  1  0  3  1  3  3  2  0  3  0  0  2  1  2  0
 0  0  0  0  0  1  1  3  2  3  3  0  1  1  0  1  0  3  3  0  2
 0  0  0  0  0  0  2  2  0  2  2  0  2  0  2  0  2  0  0  0  0

generates a code of length 21 over Z4 who´s minimum homogenous weight is 13.

Homogenous weight enumerator: w(x)=1x^0+36x^13+150x^14+220x^15+336x^16+438x^17+598x^18+856x^19+950x^20+948x^21+970x^22+928x^23+642x^24+456x^25+306x^26+168x^27+114x^28+40x^29+24x^30+4x^31+5x^32+2x^33

The gray image is a code over GF(2) with n=42, k=13 and d=13.
This code was found by Heurico 1.16 in 1.41 seconds.