000RM.dvi

1103

The rearrangementρ=ρm,n

Pick up the cards along the columns,from bottom to top, and from left
to right. Then rearrange them in the standard order.
Form=n=4, this rearrangement is the cyclic permutation of the
vertices of 4 squares:

1 2 3 4

5 6 7 8

9 10 11 12

13 14 15 16

The cycle structure is simpler after one more application: it is simply
rotation through 180 ◦about the center of the square.