A022354 Fibonacci sequence beginning 0, 20.

0, 20, 20, 40, 60, 100, 160, 260, 420, 680, 1100, 1780, 2880, 4660, 7540, 12200, 19740, 31940, 51680, 83620, 135300, 218920, 354220, 573140, 927360, 1500500, 2427860, 3928360, 6356220, 10284580

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

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).

Programs

Mathematica

a={};b=0;c=20;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 17 2008 *)
Table[20*Fibonacci[n], {n,0,50}] (* or *) LinearRecurrence[{1,1}, {0,20}, 50] (* G. C. Greubel, Aug 26 2017 *)

PARI

for(n=0,50, print1(20*fibonacci(n), ", ")) \\ G. C. Greubel, Aug 26 2017

Formula

G.f.: 20*x/(1-x-x^2). - Philippe Deléham, Nov 20 2008

a(n) = 20*A000045(n). - G. C. Greubel, Aug 26 2017