4-2'

#g2 f2 z2 n1 c2
  4x  4	%generator
  0  0  0  1
  0  0 -1  1
  0 -1  0  0
  1 -1  0  0

  4x  4	%generator
  0  0  0  1
  0  0  1  0
  0  1  0  0
  1  0  0  0

  4x  4 	% invariant form
  2 -1  0  0
 -1  2  0  0
  0  0  2 -1
  0  0 -1  2

  4x  4	% invariant form
  0  0  0  1
  0  0 -1  0
  0 -1  0  0
  1  0  0  0
4d0	%  zentr
-1
4	%  zentr
  2 0 1 -2
  0 2 2 -1
 -1 2 2  0
 -2 1 0  2
4	% normalizer
0  0  0 -1
0  0 -1  0
0  1  0  0
1  0  0  0
4d0	%  cen
-1
4	%  cen
  2 0 1 -2
  0 2 2 -1
 -1 2 2  0
 -2 1 0  2
2^3 * 3^1 = 24 %order of the group