OFFSET
0,1
COMMENTS
This is a second kind "autosequence" whose first kind companion is A022087. - Jean-François Alcover, Aug 20 2022
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
OEIS Wiki, Autosequence
Index entries for linear recurrences with constant coefficients, signature (1,1).
FORMULA
a(n) = 4*A000032(n).
a(n) = a(n-1) + a(n-2).
a(n) = A014217(n+3) - A014217(n-3), with A014217(-5) = -11, A014217(-4) = 6, A014217(-3) = -4, A014217(-2) = 2, A014217(-1) = -1 extended as proposed in A153263.
G.f. 4*(-2 + x) / (-1 + x + x^2). - R. J. Mathar, Mar 11 2011
a(n) = Lucas(n+3) - Lucas(n-3), where Lucas(i) for i = 0..2 gives -4, 3, -1. - Bruno Berselli, Jul 27 2017
MATHEMATICA
Table[4*LucasL[n], {n, 0, 30}] (* G. C. Greubel, Dec 21 2017 *)
PROG
(PARI) a(n)=4*(fibonacci(n-1)+fibonacci(n+1)) \\ Charles R Greathouse IV, Oct 16 2015
(Magma) [4*Lucas(n): n in [0..30]]; // G. C. Greubel, Dec 21 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Feb 07 2009
STATUS
approved