4-1'

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

  4x  4
  0  0  0  1
  0  0  1  0
  0  1  0  0
  1  0  0  0

  4x  4
  1  0  0  0
  0  1  0  0
  0  0  1  0
  0  0  0  1

  4x  4
  0  0  1 -1
  0  0  1  1
  1  1  0  0
 -1  1  0  0
4d0	%   zentr
-1
4x0	%   zentr
  1
  0 1
  1 1 1
 -1 1 0 1
4	% additional normalizer
 0 0  0 -1
 0 0 -1  0
 0 1  0  0
 1 0  0  0
4d0	%   cen
-1
4x0	%   cen
  1
  0 1
  1 1 1
 -1 1 0 1
2^4  = 16 %order of the group