The generator matrix

 1  0  0  0  0  1  1  1  0  1  X  X  1  1  1  X  1  1  1  X  1
 0  1  0  0  0  0  0  X  X  1  1  1  X  1  1  0  1  X  X  1  0
 0  0  1  0  0  X  1 X+1  1  0  1  1  1  X  0  1 X+1  X  1  X  0
 0  0  0  1  0 X+1  1  0  1  X X+1  1  0  0 X+1  X  X  1 X+1  1  0
 0  0  0  0  1  1  X  1  1 X+1  X  0  0  X  1 X+1  X  0 X+1  X  X

generates a code of length 21 over Z2[X]/(X^2) who´s minimum homogenous weight is 16.

Homogenous weight enumerator: w(x)=1x^0+106x^16+198x^18+231x^20+212x^22+141x^24+102x^26+33x^28

The gray image is a linear code over GF(2) with n=42, k=10 and d=16.
As d=16 is an upper bound for linear (42,10,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 10.
This code was found by Heurico 1.16 in 0.0302 seconds.