OFFSET
0,3
LINKS
Stefano Spezia, Table of n, a(n) for n = 0..10000
Index entries for linear recurrences with constant coefficients, signature (0,-3,0,-3,0,-1)
FORMULA
G.f.: (1-x-2x^3-x^5)/(1+x^2)^3.
a(n) = C(n/2+2,2)*(-1)^(n/2)*(1+(-1)^n)/2 - (-1)^((n-1)/2)*(1-(-1)^n)/2.
E.g.f.: ((8-x^2)*cos(x) - (8 + 7*x)*sin(x))/8. - Stefano Spezia, Aug 08 2025
MATHEMATICA
CoefficientList[Series[(1-x-2x^3-x^5)/(1+x^2)^3, {x, 0, 61}], x] (* Stefano Spezia, Aug 08 2025 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Paul Barry, Sep 30 2008
STATUS
approved
