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A206422
Fibonacci sequence beginning 11, 9.
1
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
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
KEYWORD
nonn,easy
AUTHOR
STATUS
approved