A131608 Period 24: repeat 1, 1, 3, 7, 7, 1, 9, 9, 7, 3, 3, 9, -1, -1, -3, -7, -7, -1, -9, -9, -7, -3, -3, -9.

1, 1, 3, 7, 7, 1, 9, 9, 7, 3, 3, 9, -1, -1, -3, -7, -7, -1, -9, -9, -7, -3, -3, -9, 1, 1, 3, 7, 7, 1, 9, 9, 7, 3, 3, 9, -1, -1, -3, -7, -7, -1, -9, -9, -7, -3, -3, -9, 1, 1, 3, 7, 7, 1, 9, 9, 7, 3, 3, 9, -1, -1, -3, -7, -7, -1, -9, -9, -7, -3, -3, -9, 1, 1, 3, 7, 7, 1, 9, 9, 7, 3, 3, 9, -1, -1, -3, -7, -7, -1, -9, -9, -7, -3, -3, -9

Offset

0,3

Links

Table of n, a(n) for n=0..95.

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,-1).

Formula

a(n)= -a(n-12).

G.f. (1+x)*(1+x+x^2)*(x^2-x+1)*(9*x^6-6*x^5+4*x^3+2*x^2+1) / ( (1+x^4)*(x^8-x^4+1) ). - R. J. Mathar, Oct 08 2011

Mathematica

PadRight[{}, 100, {1, 1, 3, 7, 7, 1, 9, 9, 7, 3, 3, 9, -1, -1, -3, -7, -7, -1, -9, -9, -7, -3, -3, -9}] (* Harvey P. Dale, Jun 09 2015 *)

Crossrefs

Sequence in context: A373862 A353049 A288093 * A131707 A348722 A349614

Adjacent sequences: A131605 A131606 A131607 * A131609 A131610 A131611

Keyword

sign,easy

Author

Paul Curtz, Oct 02 2007

Status

approved