A156536 Period 12: repeat 7,5,-1,1,-5,-7,-7,-5,1,-1,5,7.

7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5, -1, 1, -5, -7, -7, -5, 1, -1, 5, 7, 7, 5

Offset: 0

Author

Paul Curtz, Feb 09 2009

Keywords

• sign
• easy

Links

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

Crossrefs

Cf. A154870.

Programs

Mathematica

PadRight[{},120,{7,5,-1,1,-5,-7,-7,-5,1,-1,5,7}] (* or *) LinearRecurrence[{0,0,0,0,0,-1},{7,5,-1,1,-5,-7},120] (* Harvey P. Dale, Oct 15 2023 *)

Formula

a(n) = A154811(n+6) - A154811(n).

From R. J. Mathar, Apr 10 2009: (Start)

a(n) = -a(n-6).

G.f.: -(x-1)*(7*x^4 + 12*x^3 + 11*x^2 + 12*x + 7)/((1+x^2)*(x^4 - x^2 + 1)). (End)

G.f.: (-7*x^5 - 5*x^4 + x^3 - x^2 + 5*x + 7)/(x^6 + 1). - Chai Wah Wu, Feb 16 2021

Extensions

Edited by R. J. Mathar, Apr 10 2009