OFFSET
0,1
COMMENTS
For the general trisection of a sequence see a Wolfdieter Lang comment under A187357.
LINKS
Colin Barker, Table of n, a(n) for n = 0..850
Index entries for linear recurrences with constant coefficients, signature (14,1).
FORMULA
a(n) = Pell(3*n+2), n >= 0, with Pell(n):=A000129(n).
O.g.f.: (2+x)/(1-14*x-x^2).
a(n) = 14*a(n-1) + a(n-2), a(-1)=1, a(0)=2.
a(n) = (((7-5*sqrt(2))^n*(-3+2*sqrt(2)) + (3+2*sqrt(2))*(7+5*sqrt(2))^n)) / (2*sqrt(2)). - Colin Barker, Jan 25 2016
MATHEMATICA
Table[Fibonacci[3n + 2, 2], {n, 0, 20}] (* Vladimir Reshetnikov, Sep 16 2016 *)
PROG
(PARI) Vec((2+x)/(1-14*x-x^2) + O(x^20)) \\ Colin Barker, Jan 25 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Mar 09 2011
STATUS
approved