6.9.13  Order of a permutation: permuorder

If any permutation p on a finite set [0,…,n−1] is repeated often enough, it reach be the identity permutation. The smallest m such that p^m is the identity is called the order of p.

The permuorder command computes the order of a permutation.

• permuorder takes one argument:
  p, a permutation.
• permuorder(p) returns the order of the permutation p.

Examples.

• Input:
  permuorder([0,2,1])
  Output:

  2

• Input:
  permuorder([3,2,1,4,0])
  Output:

  6