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A122574
a(1) = a(2) = 1, a(n) = -11*a(n-1) + a(n-2).
2
1, 1, -10, 111, -1231, 13652, -151403, 1679085, -18621338, 206513803, -2290273171, 25399518684, -281684978695, 3123934284329, -34644962106314, 384218517453783, -4261048654097927, 47255753712530980, -524074339491938707, 5812073488123856757, -64456882708854363034
OFFSET
1,3
REFERENCES
Harry Hochstadt, The Functions of Mathematical Physics, Wiley, New York (1971), p. 170; also Dover, New York (1986), 129-130.
FORMULA
|a(n)| = A049666(n-1) - A049666(n-2), n > 1. [R. J. Mathar, Nov 02 2008]
G.f.: x*(1+12*x)/(1+11*x-x^2). [Philippe Deléham, Nov 20 2008]
MATHEMATICA
LinearRecurrence[{-11, 1}, {1, 1}, 30] (* Harvey P. Dale, Aug 11 2017 *)
PROG
(Magma) [n le 2 select 1 else -11*Self(n-1) +Self(n-2): n in [1..30]]; // G. C. Greubel, Oct 30 2024
(SageMath)
A122574=BinaryRecurrenceSequence(-11, 1, 1, 1)
[A122574(n-1) for n in range(1, 31)] # G. C. Greubel, Oct 30 2024
CROSSREFS
Cf. A049666.
Sequence in context: A078252 A014993 A015592 * A176736 A084031 A210507
KEYWORD
sign,easy
AUTHOR
Roger L. Bagula, Sep 17 2006
EXTENSIONS
Edited by N. J. A. Sloane, Dec 04 2006
STATUS
approved