A081260 a(1)=4; for n>1, a(n) is taken to be the third-smallest integer greater than a(n-1) such that the condition "n is a member of the sequence if and only if a(n) is odd" is satisfied.

4, 10, 16, 21, 26, 32, 38, 44, 50, 55, 60, 66, 72, 78, 84, 89, 94, 100, 106, 112, 117, 122, 128, 134, 140, 145, 150, 156, 162, 168, 174, 179, 184, 190, 196, 202, 208, 213, 218, 224, 230, 236, 242, 247, 252, 258, 264, 270, 276, 281, 286, 292, 298, 304, 309, 314

Offset

1,1

Links

Table of n, a(n) for n=1..56.

B. Cloitre, N. J. A. Sloane and M. J. Vandermast, Numerical analogues of Aronson's sequence, J. Integer Seqs., Vol. 6 (2003), #03.2.2.

B. Cloitre, N. J. A. Sloane and M. J. Vandermast, Numerical analogues of Aronson's sequence (math.NT/0305308)

Example

a(1)=4, implying that the fourth term is the first odd member of the sequence; hence a(2) and a(3) are even. The third-smallest even integer greater than 4 is 10; therefore a(2)=10. The third-smallest integers that can satisfy the given condition if taken as a(3) and a(4) are 16 and 21, respectively.

Crossrefs

Cf. A079000, A080753.

Sequence in context: A310511 A310512 A310513 * A310514 A190060 A328986

Adjacent sequences: A081257 A081258 A081259 * A081261 A081262 A081263

Keyword

easy,nonn

Author

Matthew Vandermast, Mar 14 2003

Status

approved