A206422 Fibonacci sequence beginning 11, 9.

11, 9, 20, 29, 49, 78, 127, 205, 332, 537, 869, 1406, 2275, 3681, 5956, 9637, 15593, 25230, 40823, 66053, 106876, 172929, 279805, 452734, 732539, 1185273, 1917812, 3103085, 5020897, 8123982, 13144879, 21268861, 34413740, 55682601, 90096341, 145778942

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

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

Formula

From Andrew Howroyd, Aug 28 2018: (Start)

a(n) = a(n-1) + a(n-2) for n > 2.

a(n) = 11*Fibonacci(n) - 2*Fibonacci(n-1).

G.f.: x*(11 - 2*x)/(1 - x - x^2). (End)

Mathematica

LinearRecurrence[{1, 1}, {11, 9}, 60]

Prog

(Magma) I:=[11, 9]; [n le 2 select I[n] else Self(n-1)+ Self(n-2): n in [1..40]]; \\ Vincenzo Librandi, Feb 18 2012
(PARI) Vec((11 - 2*x)/(1 - x - x^2) + O(x^30)) \\ Andrew Howroyd, Aug 28 2018

Crossrefs

Cf. A000045.

Sequence in context: A337227 A254716 A240757 * A316450 A196006 A196003

Adjacent sequences: A206419 A206420 A206421 * A206423 A206424 A206425

Keyword

nonn,easy

Author

Vladimir Joseph Stephan Orlovsky, Feb 07 2012

Status

approved