A118471 a(0)=1. a(n) = a(n-1)*(n+1), if n is in the sequence. a(n)= a(n-1) +1, if n is missing from the sequence.

1, 2, 6, 7, 8, 9, 63, 504, 4536, 45360, 45361, 45362, 45363, 45364, 45365, 45366, 45367, 45368, 45369, 45370, 45371, 45372, 45373, 45374, 45375, 45376, 45377, 45378, 45379, 45380, 45381, 45382, 45383, 45384, 45385, 45386, 45387, 45388

Offset

0,2

Links

Ivan Neretin, Table of n, a(n) for n = 0..1000

Mathematica

f[s_] := Block[{n = Length@s}, Append[s, If[MemberQ[s, n], s[[ -1]](n + 1), s[[ -1]] + 1]]]; Nest[f, {1}, 40] (* Robert G. Wilson v, May 16 2006 *)

Crossrefs

Sequence in context: A162917 A250183 A260139 * A167456 A023633 A332938

Adjacent sequences: A118468 A118469 A118470 * A118472 A118473 A118474

Keyword

easy,nonn

Author

Leroy Quet, May 04 2006

Status

approved