A080591 a(n) is taken to be the smallest positive 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 congruent to 3 mod 4".

1, 3, 4, 7, 11, 12, 13, 15, 16, 17, 18, 19, 23, 27, 28, 31, 35, 39, 43, 47, 48, 49, 50, 51, 52, 53, 54, 55, 59, 60, 61, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 83, 87, 91, 95, 99, 103, 107, 111, 112, 113, 114, 115, 119, 123, 124

Offset

0,2

Comments

The sequence of odd numbers shares many of the properties of this sequence.

Links

Table of n, a(n) for n=0..62.

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)) = 4n+3. a(2^k-1) = 2^(k+1)-1.

Crossrefs

a(n) = A080588(n+1) - 1. Cf. A079000.

Sequence in context: A283428 A185506 A328379 * A291063 A047543 A030489

Adjacent sequences: A080588 A080589 A080590 * A080592 A080593 A080594

Keyword

easy,nonn

Author

N. J. A. Sloane, Feb 23 2003

Status

approved