The generator matrix

 1  1  1  1
 0  7  0  7
 0  0  7 35

generates a code of length 4 over Z49 who´s minimum homogenous weight is 14.

Homogenous weight enumerator: w(x)=1x^0+36x^14+120x^21+2058x^24+186x^28

The gray image is a code over GF(7) with n=28, k=4 and d=14.
This code was found by Heurico 1.16 in 0.000138 seconds.