A080034 a(n) is taken to be the smallest positive integer not already present 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, 6, 15, 19, 9, 23, 12, 27, 31, 14, 35, 39, 17, 43, 20, 47, 51, 22, 55, 59, 25, 63, 28, 67, 71, 30, 75, 79, 33, 83, 36, 87, 91, 38, 95, 99, 41, 103, 44, 107, 111, 46, 115, 119, 49, 123, 52, 127, 131, 54, 135, 139, 57, 143, 60, 147, 151, 62, 155, 159, 65, 163

Offset

0,2

Links

Table of n, a(n) for n=0..65.

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

From Chai Wah Wu, Sep 27 2016: (Start)

a(n) = 2*a(n-8) - a(n-16) for n > 15.

G.f.: (x^15 + 5*x^14 + 2*x^13 + 9*x^12 + 13*x^11 + 4*x^10 + 17*x^9 + 7*x^8 + 19*x^7 + 15*x^6 + 6*x^5 + 11*x^4 + 7*x^3 + 4*x^2 + 3*x + 1)/(x^16 - 2*x^8 + 1). (End)

Crossrefs

Equals A080033(n+1)-1.

Sequence in context: A291609 A291870 A002887 * A378030 A061447 A219188

Adjacent sequences: A080031 A080032 A080033 * A080035 A080036 A080037

Keyword

easy,nonn

Author

N. J. A. Sloane, Mar 14 2003

Extensions

More terms from Matthew Vandermast, Mar 23 2003

Status

approved