OFFSET
1,1
LINKS
Index entries for linear recurrences with constant coefficients, signature (-1,-1,1,1,1).
FORMULA
a(n) = sin(n*Pi/3)*((8n+6)*sin(n*Pi/3)-5*sqrt(3)*cos(n*Pi))*(-1)^floor(2n/3)/9. - Wesley Ivan Hurt, Sep 24 2017
From Chai Wah Wu, Feb 03 2021: (Start)
a(n) = - a(n-1) - a(n-2) + a(n-3) + a(n-4) + a(n-5) for n > 5.
G.f.: x*(-x^3 - x^2 - x - 2)/((x - 1)*(x^2 + x + 1)^2). (End)
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Paul Curtz, Sep 14 2007
STATUS
approved