%I #17 Sep 08 2022 08:44:55
%S 1,12,577,6936,333505,4008996,192765313,2317192752,111418017409,
%T 1339333401660,64399421297089,774132388966728,37222754091700033,
%U 447447181489367124,21514687465581321985,258623696768465230944,12435452132351912407297,149484049284991414118508
%N Denominators of continued fraction convergents to sqrt(580).
%H Vincenzo Librandi, <a href="/A042111/b042111.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,578,0,-1).
%F G.f.: -(x^2-12*x-1) / ((x^2-24*x-1)*(x^2+24*x-1)). - _Colin Barker_, Dec 02 2013
%F a(n) = 578*a(n-2) - a(n-4) for n>3. - _Vincenzo Librandi_, Jan 15 2014
%t Denominator[Convergents[Sqrt[580], 30]] (* _Vincenzo Librandi_, Jan 15 2014 *)
%o (Magma) I:=[1,12,577,6936]; [n le 4 select I[n] else 578*Self(n-2)-Self(n-4): n in [1..30]]; // _Vincenzo Librandi_, Jan 15 2014
%Y Cf. A042110, A040555.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Dec 02 2013
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