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%I #40 Oct 30 2024 11:41:56
%S 1,1,-10,111,-1231,13652,-151403,1679085,-18621338,206513803,
%T -2290273171,25399518684,-281684978695,3123934284329,-34644962106314,
%U 384218517453783,-4261048654097927,47255753712530980,-524074339491938707,5812073488123856757,-64456882708854363034
%N a(1) = a(2) = 1, a(n) = -11*a(n-1) + a(n-2).
%D Harry Hochstadt, The Functions of Mathematical Physics, Wiley, New York (1971), p. 170; also Dover, New York (1986), 129-130.
%H Indranil Ghosh, <a href="/A122574/b122574.txt">Table of n, a(n) for n = 1..958</a>
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (-11,1).
%F |a(n)| = A049666(n-1) - A049666(n-2), n > 1. [_R. J. Mathar_, Nov 02 2008]
%F G.f.: x*(1+12*x)/(1+11*x-x^2). [_Philippe Deléham_, Nov 20 2008]
%t LinearRecurrence[{-11,1},{1,1},30] (* _Harvey P. Dale_, Aug 11 2017 *)
%o (Magma) [n le 2 select 1 else -11*Self(n-1) +Self(n-2): n in [1..30]]; // _G. C. Greubel_, Oct 30 2024
%o (SageMath)
%o A122574=BinaryRecurrenceSequence(-11,1,1,1)
%o [A122574(n-1) for n in range(1,31)] # _G. C. Greubel_, Oct 30 2024
%Y Cf. A049666.
%K sign,easy
%O 1,3
%A _Roger L. Bagula_, Sep 17 2006
%E Edited by _N. J. A. Sloane_, Dec 04 2006