The generator matrix
1 0 1 1 1 X 1 1 0 1 1 X 1 1 1 1 0 X 1 1 1 1 0 X X X 0 1 1 1 1 0 X X X 0 1 1 1 1 1 1
0 1 X+1 X 1 1 0 X+1 1 X 1 1 0 X X+1 1 1 1 0 X X+1 1 1 1 0 X X 0 X X+1 1 1 1 0 X X 0 X X+1 1 0 X
generates a code of length 42 over Z2[X]/(X^2) who´s minimum homogenous weight is 44.
Homogenous weight enumerator: w(x)=1x^0+13x^44+1x^48+1x^52
The gray image is a linear code over GF(2) with n=84, k=4 and d=44.
As d=44 is an upper bound for linear (84,4,2)-codes, this code is optimal over Z2[X]/(X^2) for dimension 4.
This code was found by Heurico 1.16 in 0.011 seconds.