A022371 Fibonacci sequence beginning 2, 18.

2, 18, 20, 38, 58, 96, 154, 250, 404, 654, 1058, 1712, 2770, 4482, 7252, 11734, 18986, 30720, 49706, 80426, 130132, 210558, 340690, 551248, 891938, 1443186, 2335124, 3778310, 6113434, 9891744, 16005178

Offset

0,1

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Tanya Khovanova, Recursive Sequences

Index entries for linear recurrences with constant coefficients, signature (1, 1).

Formula

G.f.: (2+16*x)/(1-x-x^2). - Philippe Deléham, Nov 19 2008

a(n) = 2*(Fibonacci(n+2) + 7*Fibonacci(n)). - G. C. Greubel, Aug 27 2017

a(n) = 2 * A022099(n). - Alois P. Heinz, Aug 27 2017

Mathematica

a={}; b=2; c=18; AppendTo[a, b]; AppendTo[a, c]; Do[b=b+c; AppendTo[a, b]; c=b+c; AppendTo[a, c], {n, 4!}]; a (* Vladimir Joseph Stephan Orlovsky, Sep 18 2008 *)
Transpose[NestList[{Last[#], Total[#]}&, {2, 18}, 30]][[1]]  (* Harvey P. Dale, Apr 13 2011 *)
LinearRecurrence[{1, 1}, {2, 18}, 40] (* Harvey P. Dale, Jun 26 2021 *)

Prog

(PARI) for(n=0, 50, print1(2*(fibonacci(n+2) + 7*fibonacci(n)), ", ")) \\ G. C. Greubel, Aug 27 2017

Crossrefs

Cf. A022099.

Sequence in context: A231502 A231864 A066242 * A299380 A352159 A266956

Adjacent sequences: A022368 A022369 A022370 * A022372 A022373 A022374

Keyword

nonn

Author

N. J. A. Sloane

Status

approved