The generator matrix

 1  0  0  0  1  1  1  2 10  1 12  1  1  1 14 12 14  0  1  6  1  1  0  1 12  1  1  1  1 14 12  1  1 14 12  1 10  1  2  4  1  1  2  1  4 12  1 12 10  1  1 10  1  1  1  1 10  2 10  1  1  1  1  1
 0  1  0  0  0  9  5  1  1  8  1  4  7 11  0  1 10 10  2  1 10  5  1  7  1  4  1 12 13  1  1  9 11  6  4 11  1  4  0  1 12  3  4  6 10  8 14  1  1  7  0  1  9 14  8  1  1  1 12  2 11 13  6  0
 0  0  1  0  1  1  4  5  2 10  3  3 12  5  1  5  1 14  3 10 14  7  8  8 13  4 10  3 15  9 14 13  6  1  1  4 15  0  1  2 15  5  1  2 12  1  8 14 14  3  5  4 10 11 12  7  2  9 14  8  5  8 13  0
 0  0  0  1  1  4  1  1 15  9  6 10 14 11  9  5  3  1  1 10  7 11 11 11  2  2  6 12  6 15 11 13 11  8  9 12  8  5 14 12 15  9 15  6  1 14  6  5  1  0  7  5  7  0  0  9 12  1  1  3 12 12  7  0
 0  0  0  0 12  0  0  0  0  0  0  0  0  0  0  0  0  0  8  8  8  8  8  8 12 12  4 12  4 12 12  4  4  4 12  4  4  4  4 12  8  8  4  0  4  8 12  4  8  4 12  8 12  8 12 12  4  4  4  8 12 12  8  0

generates a code of length 64 over Z16 who´s minimum homogenous weight is 55.

Homogenous weight enumerator: w(x)=1x^0+86x^55+720x^56+1948x^57+4682x^58+7866x^59+13963x^60+21602x^61+27362x^62+34640x^63+35649x^64+34772x^65+29045x^66+21322x^67+13677x^68+7790x^69+4114x^70+1674x^71+704x^72+318x^73+103x^74+56x^75+22x^76+16x^77+6x^78+4x^79+2x^81

The gray image is a code over GF(2) with n=512, k=18 and d=220.
This code was found by Heurico 1.16 in 576 seconds.