The generator matrix

 1  0  1  1  1  1  1  X  1  1  1 2X  1  1  1  1  1  1  1  1
 0  1 2X+1  2  X X+1 X+2  1 2X  1 2X+2  1  0  X 2X+1 X+1 2X  1  2 X+2

generates a code of length 20 over Z3[X]/(X^2) who´s minimum homogenous weight is 39.

Homogenous weight enumerator: w(x)=1x^0+12x^39+54x^40+10x^42+2x^45+2x^51

The gray image is a linear code over GF(3) with n=60, k=4 and d=39.
As d=39 is an upper bound for linear (60,4,3)-codes, this code is optimal over Z3[X]/(X^2) for dimension 4.
This code was found by Heurico 1.16 in 0.000801 seconds.