A132196 a(2n+1) = 2a(2n)-n for the odd indices. Smallest strictly positive integer not yet in the list for the even indices, a(2n).

1, 2, 3, 5, 4, 6, 7, 11, 8, 12, 9, 13, 10, 14, 15, 23, 16, 24, 17, 25, 18, 26, 19, 27, 20, 28, 21, 29, 22, 30, 31, 47, 32, 48, 33, 49, 34, 50, 35, 51, 36, 52, 37, 53, 38, 54, 39, 55, 40, 56, 41, 57, 42, 58, 43, 59, 44, 60, 45, 61, 46, 62, 63, 95, 64, 96, 65, 97, 66, 98, 67, 99

Offset

0,2

Links

Ivan Neretin, Table of n, a(n) for n = 0..10000

Formula

a(n) = m + (n-1)/2 for odd n and a(n) = (m + n)/2 for even n, where m is the greatest power of 2 not exceeding n+2. - Ivan Neretin, Sep 05 2017

Mathematica

Fold[Append[#1, If[OddQ[#2], 2 #1[[-1]] - (#2 - 1)/2, Min@Complement[Range[Max[#1] + 1], #1]]] &, {1}, Range[71]] (* Ivan Neretin, Sep 04 2017 *)

Crossrefs

Sequence in context: A154443 A180200 A121216 * A153150 A069766 A081241

Adjacent sequences: A132193 A132194 A132195 * A132197 A132198 A132199

Keyword

nonn

Author

Paul Curtz, Nov 05 2007

Extensions

Edited by R. J. Mathar, Nov 16 2007

Status

approved