The generator matrix

 1  0  0  1  1  1  1  1 5X  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1 5X  1  1  1  1  1  1  1 2X
 0  1  0 5X+1  3 5X+2 5X 5X+3  1  6  1 4X+2 5X+6  4  5 4X 4X+1 2X+2 2X+4 X+3 6X+4 3X+5 X+4 2X+5 X+2 2X+6 5X+6 3X+1 5X+5 3X 4X+6 3X+3 5X+2  1 5X 6X+3  X 5X+5 6X+5  4 2X+6  0 3X+4 4X+2  1
 0  0  1 5X+5  3 5X+6 5X+1 5X+4 5X+2 X+3 X+2  X 4X+4  2 3X+5 4X+2 X+6 3X+3 6X+4 6X+5 3X+6 5X  1 6X+1  5 5X+6 3X+1 6X+4 2X+3 2X+6 2X+4 2X 4X+6 4X+1  4 2X+3  1 3X+3 6X 2X+2 2X+1 5X 6X+3 6X+1 5X+3

generates a code of length 45 over Z7[X]/(X^2) who´s minimum homogenous weight is 256.

Homogenous weight enumerator: w(x)=1x^0+2436x^256+3570x^257+42x^258+354x^259+1260x^260+2394x^261+2394x^262+10248x^263+9828x^264+504x^265+1380x^266+3360x^267+4032x^268+2268x^269+13356x^270+14322x^271+1512x^272+2628x^273+5670x^274+5922x^275+3570x^276+15120x^277+11382x^278+36x^280+30x^287+12x^294+6x^301+12x^308

The gray image is a linear code over GF(7) with n=315, k=6 and d=256.
This code was found by Heurico 1.16 in 3.03 seconds.