The generator matrix

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

generates a code of length 42 over Z7[X]/(X^2) who´s minimum homogenous weight is 231.

Homogenous weight enumerator: w(x)=1x^0+240x^231+498x^238+420x^245+14808x^252+234x^259+168x^266+246x^273+102x^280+84x^287+6x^294

The gray image is a linear code over GF(7) with n=294, k=5 and d=231.
This code was found by Heurico 1.16 in 0.191 seconds.