Perfect Shuffle Permutation
This was advised by Harold Stone (1971). Consider N objects each characterized by n bit number say Xn-1, Xn-2, X0 (N is chosen such that N = 2n.) The ideal shuffle of these N objects is expressed as
X n-1, X n-2, X0 = X n-2, X 0 X n-1.
It means perfect shuffle is achieved by rotating the address by 1 bit left. E.g. shuffle of 8 objects is shown below as:-