A206612 Fibonacci sequence beginning 13, 6.

13, 6, 19, 25, 44, 69, 113, 182, 295, 477, 772, 1249, 2021, 3270, 5291, 8561, 13852, 22413, 36265, 58678, 94943, 153621, 248564, 402185, 650749, 1052934, 1703683, 2756617, 4460300, 7216917, 11677217, 18894134, 30571351, 49465485, 80036836, 129502321

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) = 13*Fibonacci(n) - 7*Fibonacci(n-1).

G.f.: x*(13 - 7*x)/(1 - x - x^2).

(End)

Mathematica

LinearRecurrence[{1, 1}, {13, 6}, 80]

Prog

(Magma) I:=[13, 6]; [n le 2 select I[n] else Self(n-1)+Self(n-2): n in [1..40]]; \\ Vincenzo Librandi, Feb 17 2012
(PARI) Vec((13 - 7*x)/(1 - x - x^2) + O(x^30)) \\ Andrew Howroyd, Aug 28 2018

Crossrefs

Cf. A000032, A000045, A206610, A206611.

Sequence in context: A004478 A300504 A168210 * A220131 A268723 A300942

Adjacent sequences: A206609 A206610 A206611 * A206613 A206614 A206615

Keyword

nonn,easy

Author

Vladimir Joseph Stephan Orlovsky, Feb 10 2012

Status

approved