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%I #21 Jun 26 2022 23:55:30
%S 1,1,2,3,5,43,48,91,139,230,12559,12789,25348,38137,63485,546017,
%T 609502,1155519,1765021,2920540,159474181,162394721,321868902,
%U 484263623,806132525,6933323823,7739456348,14672780171,22412236519,37085016690,2025003137779
%N Denominators of continued fraction convergents to sqrt(762).
%H Vincenzo Librandi, <a href="/A042469/b042469.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_20">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 12698, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^4 - 3*x^3 + 4*x^2 - 2*x + 1)*(x^4 + 2*x^3 + 4*x^2 + 3*x + 1)*(x^10 - 46*x^5 - 1) / (x^20 - 12698*x^10 + 1). - _Colin Barker_, Dec 15 2013
%F a(n) = 12698*a(n-10) - a(n-20) for n > 19. - _Vincenzo Librandi_, Jan 23 2014
%t Denominator[Convergents[Sqrt[762], 30]] (* _Harvey P. Dale_, Feb 20 2013 *)
%o (Magma) I:=[1,1,2,3,5,43,48,91,139,230,12559,12789,25348, 38137,63485,546017,609502,1155519,1765021,2920540]; [n le 20 select I[n] else 12698*Self(n-10)-Self(n-20): n in [1..40]]; // _Vincenzo Librandi_, Jan 23 2014
%Y Cf. A042468, A040734.
%K nonn,frac,easy
%O 0,3
%A _N. J. A. Sloane_
%E More terms from _Colin Barker_, Dec 15 2013
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