A118550 a(0)=1; a(n) = a(n-1) + n if n is in the sequence, a(n) = a(n-1) + 1 if n is missing from the sequence.

1, 2, 4, 5, 9, 14, 15, 16, 17, 26, 27, 28, 29, 30, 44, 59, 75, 92, 93, 94, 95, 96, 97, 98, 99, 100, 126, 153, 181, 210, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311

Offset

0,2

Links

Table of n, a(n) for n=0..58.

Mathematica

f[s_] := Block[{n = Length@s}, Append[s, If[ MemberQ[s, n], 2s[[ -1]], s[[ -1]] + 1]]]; Nest[f, {1}, 60] (* Robert G. Wilson v, May 17 2006 *)

Crossrefs

Sequence in context: A357488 A060167 A234588 * A126697 A162406 A129282

Adjacent sequences: A118547 A118548 A118549 * A118551 A118552 A118553

Keyword

easy,nonn

Author

Leroy Quet, May 03 2006

Extensions

More terms from Robert G. Wilson v, May 17 2006

Status

approved