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%I #15 Sep 08 2022 08:44:54
%S 1,3,109,330,11989,36297,1318681,3992340,145042921,439121103,
%T 15953402629,48299328990,1754729246269,5312487067797,193004263686961,
%U 584325278128680,21228714276319441,64270468107087003,2334965566131451549,7069167166501441650
%N Denominators of continued fraction convergents to sqrt(336).
%H Vincenzo Librandi, <a href="/A041635/b041635.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 (0,110,0,-1).
%F G.f.: -(x^2-3*x-1) / (x^4-110*x^2+1). - _Colin Barker_, Nov 20 2013
%F a(n) = 110*a(n-2) - a(n-4) for n>3. - _Vincenzo Librandi_, Dec 22 2013
%t Denominator[Convergents[Sqrt[336], 30]] (* _Vincenzo Librandi_, Dec 22 2013 *)
%o (Magma) I:=[1,3,109,330]; [n le 4 select I[n] else 110*Self(n-2)-Self(n-4): n in [1..40]]; // _Vincenzo Librandi_, Dec 22 2013
%Y Cf. A041634, A040317.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E Additional term from _Colin Barker_, Nov 20 2013