OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (1,1,-1,-1,1).
FORMULA
G.f.: x(1+3x+x^2)/((1-x)(1-x^2+x^4)) = x(1+3x+x^2)/(1-x-x^2+x^3+x^4-x^5).
a(n) = a(n-1) + a(n-2) - a(n-3) - a(n-4) + a(n-5).
a(n) = (sqrt(8) - sqrt(6))*cos(5*Pi*n/6 + 5*Pi/12)-(sqrt(8) + sqrt(6))*cos(Pi*n/6 + Pi/12) + 5.
a(n + 12) = a(n). - G. C. Greubel, May 18 2016
MATHEMATICA
LinearRecurrence[{1, 1, -1, -1, 1}, {0, 1, 4, 6, 9}, 25] (* G. C. Greubel, May 18 2016 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Oct 17 2009
STATUS
approved