OFFSET
0,1
LINKS
FORMULA
a(n) = ((2+sqrt(3))^n+(2-sqrt(3))^n)/2.
a(n) = A001075(n)+1.
From R. J. Mathar, Aug 07 2008: (Start)
a(n) = A102206(n-1).
G.f.: (1-3*x)*(x-2)/((x-1)*(x^2-4*x+1)). (End)
a(n) = 5*a(n-1) - 5*a(n-2) + a(n-3). - Wesley Ivan Hurt, Jan 16 2024
MATHEMATICA
Table[((-1+Sqrt[3])^n+(1+Sqrt[3])^n)^2/(2^(n+1)), {n, 0, 25}]
LinearRecurrence[{5, -5, 1}, {2, 3, 8}, 25] (* Ray Chandler, Jan 27 2014 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Sep 06 2006
STATUS
approved