The generator matrix

 1  0  1  1  1  6  1  1  4  1  2  1  1  1  6  6  1  1  4  4  1  1  1  1  1  1  1  1  4  1  1  1  1  1  1  0  1  1  0  1  1  1  1  4  0  1  1  1  2  1  1  1  6  1  1  4  4  1  4  1  1  2  6  2
 0  1  1  0  3  1  3  6  1  2  1  5  4  3  1  1  7  2  1  1  5  2  0  7  5  6  0  3  1  1  7  0  2  7  1  1  0  2  1  3  4  5  5  1  1  4  1  1  1  1  0  6  1  1  0  1  1  0  1  2  1  2  1  4
 0  0  2  0  6  0  4  4  2  6  6  4  6  2  2  4  4  2  0  2  4  0  6  2  2  4  0  0  6  0  4  6  6  0  2  2  0  0  0  2  6  6  4  2  0  6  6  4  2  4  4  0  6  0  2  4  0  2  2  2  6  2  6  6
 0  0  0  2  0  0  0  4  4  4  0  0  4  2  2  6  2  2  6  6  2  2  6  2  6  0  6  4  4  6  6  4  2  4  0  2  0  2  0  6  0  0  2  4  2  0  4  4  6  4  6  0  4  4  2  4  6  6  0  2  2  4  6  2
 0  0  0  0  4  0  0  0  4  4  4  0  4  4  4  0  0  4  0  4  0  4  0  0  0  4  4  4  0  4  4  0  0  4  0  0  4  0  4  4  0  4  4  0  0  4  4  0  0  4  0  0  4  4  0  0  4  0  0  4  4  0  0  4
 0  0  0  0  0  4  4  4  0  4  4  0  0  0  0  0  4  4  4  4  0  0  4  4  0  4  4  4  0  0  4  4  0  0  4  4  0  4  4  0  0  0  4  4  0  4  4  4  0  0  4  4  0  4  0  4  4  0  4  0  0  0  0  4

generates a code of length 64 over Z8 who´s minimum homogenous weight is 57.

Homogenous weight enumerator: w(x)=1x^0+110x^57+182x^58+206x^59+325x^60+400x^61+353x^62+338x^63+365x^64+332x^65+413x^66+376x^67+225x^68+162x^69+113x^70+82x^71+27x^72+10x^73+18x^74+14x^75+14x^76+10x^77+5x^78+8x^79+3x^80+3x^82+1x^86

The gray image is a code over GF(2) with n=256, k=12 and d=114.
This code was found by Heurico 1.16 in 0.859 seconds.