The generator matrix

 1  0  1  1  1  1  1  1  1  1  1  7  1  1  1  1  1 21
 0  1 36 31 16 48  7 29 38  9  6  1 21 43  3 23 20  1

generates a code of length 18 over Z49 who´s minimum homogenous weight is 104.

Homogenous weight enumerator: w(x)=1x^0+756x^104+36x^105+588x^108+1008x^111+12x^126

The gray image is a code over GF(7) with n=126, k=4 and d=104.
This code was found by Heurico 1.16 in 0.0133 seconds.