OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3,-4,4,-3,1).
FORMULA
From Colin Barker, Mar 23 2018: (Start)
G.f.: (1 + 3*x + x^2 + 3*x^3 + x^4)/((1 - x)^3*(1 + x^2)).
a(n) = 3*a(n-1) - 4*a(n-2) + 4*a(n-3) - 3*a(n-4) + a(n-5) for n > 4.
(End)
From Stefano Spezia, Jan 30 2023: (Start)
a(n) = (5 + 9*n*(1 + n) - A087960(n))/4.
E.g.f.: (exp(x)*(5 + 18*x + 9*x^2) - cos(x) + sin(x))/4. (End)
PROG
(PARI) Vec((1 + 3*x + x^2 + 3*x^3 + x^4) / ((1 - x)^3*(1 + x^2)) + O(x^60)) \\ Colin Barker, Mar 23 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Mar 23 2018
STATUS
approved