OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (2,0,-1).
FORMULA
From R. J. Mathar, Apr 07 2011: (Start)
G.f.: -x*(-5 + 4*x)/((x - 1)*(x^2 + x - 1)).
a(n) = A022096(n) - 1. (End)
a(n) = 6*F(n) + F(n-1) - 1, where F = A000045. - Bruno Berselli, Feb 20 2017
From Colin Barker, Feb 20 2017: (Start)
a(n) = -1 + (2^(-1-n)*((1-t)^n*(-11+t) + (1+t)^n*(11+t))) / t where t=sqrt(5).
a(n) = 2*a(n-1) - a(n-3) for n>2. (End)
MATHEMATICA
LinearRecurrence[{2, 0, -1}, {0, 5, 6}, 60] (* Vladimir Joseph Stephan Orlovsky, Feb 11 2012 *)
PROG
(PARI) concat(0, Vec(x*(5-4*x) / ((1-x)*(1-x-x^2)) + O(x^50))) \\ Colin Barker, Feb 20 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved