A080640 a(1) = 3; for n>1, a(n) is taken to be the smallest integer greater than a(n-1) which is consistent with the condition "n is a member of the sequence if and only if a(n) is divisible by 4".

3, 5, 8, 9, 12, 13, 14, 16, 20, 21, 22, 24, 28, 32, 33, 36, 37, 38, 39, 40, 44, 48, 49, 52, 53, 54, 55, 56, 57, 58, 59, 60, 64, 65, 66, 68, 72, 76, 80, 84, 85, 86, 87, 88, 89, 90, 91, 92, 96, 97, 98, 100, 104, 108, 112, 116, 120, 124, 128, 132, 133, 134, 135, 136, 140, 144

Offset

1,1

Links

Table of n, a(n) for n=1..66.

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)

Index entries for sequences of the a(a(n)) = 2n family

Formula

{a(a(n))} = {6, 4i, i >= 3}.

Crossrefs

Cf. A080639, A079000.

Sequence in context: A292526 A151747 A088597 * A189164 A189032 A189130

Adjacent sequences: A080637 A080638 A080639 * A080641 A080642 A080643

Keyword

nonn,easy

Author

N. J. A. Sloane and Benoit Cloitre, Feb 28 2003

Extensions

More terms from Matthew Vandermast, Feb 28 2003

Status

approved