A102569 Inverse permutation to A102568.

1, 2, 4, 3, 5, 6, 8, 9, 11, 12, 14, 7, 15, 16, 18, 10, 19, 20, 22, 13, 23, 24, 26, 27, 29, 30, 32, 17, 33, 34, 36, 37, 39, 40, 42, 21, 43, 44, 46, 47, 49, 50, 52, 25, 53, 54, 56, 28, 57, 58, 60, 31, 61, 62, 64, 65, 67, 68, 70, 35, 71, 72, 74, 38, 75, 76, 78, 41, 79, 80, 82, 83

Offset: 1

Author

Reinhard Zumkeller, Jan 15 2005

Keywords

• nonn

Comments

A102571(n) = a(a(n)).

Links

• Index entries for sequences that are permutations of the natural numbers

Programs

Mathematica

nt = 100; (* number of output terms *)
nmax = 150; (* needed length of A102568 *)
A102568 = Nest[Append[#, If[#[[-1]] == #[[-2]]+1, 2 #[[-1]], Min[Complement[Range[Max[#]+1], #]]]]&, {1, 2}, nmax];
Do[a[A102568[[n]]] = n, {n, 1, nmax}];
Table[a[n], {n, 1, nt}] (* Jean-François Alcover, May 03 2023, after Ivan Neretin for A102568 *)