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%I #29 Dec 23 2023 09:45:27
%S 0,1,9,76,639,5371,45144,379441,3189249,26806036,225308079,1893742531,
%T 15917142384,133785568801,1124484407289,9451431821596,79440464357919,
%U 667707020113291,5612160859230024,47170912632503761,396477409396383729,3332442121404934756
%N a(n) = 9*a(n-1) - 5*a(n-2), with a(0)=0, a(1)=1.
%H G. C. Greubel, <a href="/A190982/b190982.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (9,-5).
%F G.f.: x/(1 - 9*x + 5*x^2). - _Philippe Deléham_, Oct 12 2011
%F E.g.f.: (2/sqrt(61))*exp(9*x/2)*sinh(sqrt(61)*x/2). - _G. C. Greubel_, Aug 26 2022
%t LinearRecurrence[{9,-5}, {0,1}, 50]
%o (Magma) [Round(5^((n-1)/2)*Evaluate(ChebyshevU(n), 9/(2*Sqrt(5)))): n in [0..30]]; // _G. C. Greubel_, Aug 26 2022
%o (SageMath)
%o A190982 = BinaryRecurrenceSequence(9,-5,0,1)
%o [A190982(n) for n in (0..30)] # _G. C. Greubel_, Aug 26 2022
%Y Cf. A190958 (index to generalized Fibonacci sequences).
%K nonn
%O 0,3
%A _Vladimir Joseph Stephan Orlovsky_, May 24 2011