T^(0) =
     1  0  0  0
     0  1  1  1
     0  1  1  0
     1  0  1  1

T^(1) =
     1  0  0  0
     0  1  1  1
     0  1  1  0
     1  0  1  1

T^(2) =
     1  0  0  0
     0  1  1  1
     0  1  1  1
     1  0  1  1

T^(3) =
     1  0  0  0
     0  1  1  1
     0  1  1  1
     1  1  1  1

T^(4) =
     1  0  0  0
     1  1  1  1
     1  1  1  1
     1  1  1  1

Edges of the transitive closure G* (excluding self-loops):
   (2,1) (2,3) (2,4) (3,1) (3,2) (3,4) (4,1) (4,2) (4,3)
