A080708 a(1)=5; for n>1, a(n) = smallest number > a(n-1) such that the condition "n is in the sequence if and only if a(n) is a multiple of 4" is satisfied.

5, 6, 7, 9, 12, 16, 20, 21, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 40, 41, 42, 44, 48, 52, 53, 56, 60, 64, 68, 72, 76, 80, 84, 88, 89, 90, 91, 92, 96, 100, 101, 104, 105, 106, 107, 108, 109, 110, 111, 112, 116, 117, 118, 120, 121, 122, 123, 124, 125, 126, 127

Offset

1,1

Links

Table of n, a(n) for n=1..63.

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)

Formula

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

Crossrefs

Sequence in context: A072956 A241203 A279001 * A047576 A123123 A308892

Adjacent sequences: A080705 A080706 A080707 * A080709 A080710 A080711

Keyword

nonn,easy

Author

Benoit Cloitre, Mar 01 2003

Extensions

More terms from Matthew Vandermast, Mar 14 2003

Status

approved