// output of ./demo/perm/permrand-self-inverse-demo.cc:
// Description:
//% Random involutions (self-inverse permutations).

arg 1: 8 == n  [Involutions of n elements]  default=8
arg 2: 20 == c  [Number of permutations]  default=20
   0:    [ 7 4 2 5 1 3 6 0 ]  Ind
   1:    [ 6 4 3 2 1 7 0 5 ]  Ind  Der
   2:    [ 0 2 1 7 5 4 6 3 ]
   3:    [ 0 5 2 4 3 1 6 7 ]
   4:    [ 4 6 3 2 0 7 1 5 ]  Ind  Der
   5:    [ 3 5 4 0 2 1 7 6 ]  Der
   6:    [ 6 1 2 7 4 5 0 3 ]  Ind
   7:    [ 0 1 3 2 4 5 7 6 ]
   8:    [ 0 5 4 3 2 1 6 7 ]
   9:    [ 1 0 7 5 6 3 4 2 ]  Der
  10:    [ 5 7 2 6 4 0 3 1 ]  Ind
  11:    [ 6 7 2 3 5 4 0 1 ]  Ind
  12:    [ 0 7 4 6 2 5 3 1 ]
  13:    [ 4 5 6 7 0 1 2 3 ]  Ind  Der
  14:    [ 0 1 4 5 2 3 7 6 ]
  15:    [ 2 1 0 6 4 7 3 5 ]
  16:    [ 3 1 2 0 7 5 6 4 ]
  17:    [ 0 3 4 1 2 5 7 6 ]
  18:    [ 6 7 5 3 4 2 0 1 ]  Ind
  19:    [ 4 3 5 1 0 2 6 7 ]