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%I #14 Sep 08 2022 08:44:54
%S 1,7,197,1386,39005,274421,7722793,54333972,1529074009,10757852035,
%T 302748930989,2130000368958,59942759261813,421729315201649,
%U 11868363584907985,83500274409557544,2349876047052519217,16532632603777192063,465263588952813896981
%N Denominators of continued fraction convergents to sqrt(200).
%H Vincenzo Librandi, <a href="/A041371/b041371.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 (0,198,0,-1).
%F G.f.: -(x^2-7*x-1) / ((x^2-14*x-1)*(x^2+14*x-1)). - _Colin Barker_, Nov 16 2013
%F a(n) = 198*a(n-2) - a(n-4). - _Vincenzo Librandi_, Dec 16 2013
%t Denominator[Convergents[Sqrt[200], 30]] (* _Vincenzo Librandi_, Dec 16 2013 *)
%o (Magma) I:=[1,7,197,1386]; [n le 4 select I[n] else 198*Self(n-2)-Self(n-4): n in [1..30]]; // _Vincenzo Librandi_, Dec 16 2013
%Y Cf. A041370, A040185.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Nov 16 2013