The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1
 0  7  0  7 21 21  0  7 21 14 14 14 42
 0  0  7 35 21 14 28 14  7 35  7 42 42

generates a code of length 13 over Z49 who´s minimum homogenous weight is 70.

Homogenous weight enumerator: w(x)=1x^0+120x^70+108x^77+2058x^78+48x^84+66x^91

The gray image is a code over GF(7) with n=91, k=4 and d=70.
This code was found by Heurico 1.16 in 0.00119 seconds.