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%I #22 Sep 08 2022 08:44:55
%S 1,2,3,5,13,811,1635,2446,4081,10608,661777,1334162,1995939,3330101,
%T 8656141,540010843,1088677827,1628688670,2717366497,7063421664,
%U 440649509665,888362440994,1329011950659,2217374391653,5763760733965,359570539897483,724904840528931
%N Denominators of continued fraction convergents to sqrt(985).
%H Vincenzo Librandi, <a href="/A042907/b042907.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 816, 0, 0, 0, 0, 1).
%F G.f.: -(x^8-2*x^7+3*x^6-5*x^5+13*x^4+5*x^3+3*x^2+2*x+1) / (x^10+816*x^5-1). - _Colin Barker_, Dec 25 2013
%F a(n) = 816*a(n-5) + a(n-10) for n>9. - _Vincenzo Librandi_, Feb 01 2014
%t Denominator[Convergents[Sqrt[985], 30]] (* _Vincenzo Librandi_, Feb 01 2014 *)
%t LinearRecurrence[{0,0,0,0,816,0,0,0,0,1},{1,2,3,5,13,811,1635,2446,4081,10608},30] (* _Harvey P. Dale_, Jan 01 2017 *)
%o (Magma) I:=[1,2,3,5,13,811,1635,2446,4081,10608]; [n le 10 select I[n] else 816*Self(n-5)+Self(n-10): n in [1..30]]; // _Vincenzo Librandi_, Feb 01 2014
%Y Cf. A042906, A040953.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Dec 25 2013
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