A072099 First term = 1 and, for each n > 1, n*a(n) does not appear.

1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77

Offset

1,2

Comments

Does lim_{n->infinity} (a(n)-n)/sqrt(n) = 1?

Links

Ivan Neretin, Table of n, a(n) for n = 1..10000

Example

a(2) = 2 so 2*2 = 4 is not in the sequence. a(4) = 5 so 4*5 = 20 is not in the sequence. There is no n such that n*a(n) = 3, so 3 is in the sequence.

Mathematica

Nest[Append[#, Min@Complement[Range[#[[-1]]*Length@# + 1], #, #*Range@Length@#]] &, {1}, 70] (* Ivan Neretin, Dec 20 2017 *)

Crossrefs

For complement see A297190.

Sequence in context: A213367 A175084 A171519 * A046841 A244218 A164514

Adjacent sequences: A072096 A072097 A072098 * A072100 A072101 A072102

Keyword

easy,nonn

Author

Benoit Cloitre, Jun 18 2002

Extensions

Name changed by Franklin T. Adams-Watters, Aug 21 2013

Status

approved