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Denominators of continued fraction convergents to sqrt(820).
2

%I #16 Jun 13 2015 00:49:46

%S 1,1,2,3,8,11,118,129,376,505,881,1386,78497,79883,158380,238263,

%T 634906,873169,9366596,10239765,29846126,40085891,69932017,110017908,

%U 6230934865,6340952773,12571887638,18912840411,50397568460,69310408871,743501657170

%N Denominators of continued fraction convergents to sqrt(820).

%H Vincenzo Librandi, <a href="/A042583/b042583.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 (0,0,0,0,0,0,0,0,0,0,0,79378,0,0,0,0,0,0,0,0,0,0,0,-1).

%F G.f.: -(x^2 -x -1)*(x^20 +3*x^18 +11*x^16 +129*x^14 +505*x^12 +1386*x^10 +505*x^8 +129*x^6 +11*x^4 +3*x^2 +1) / ((x^8 -43*x^4 +1)*(x^16 +43*x^12 +1848*x^8 +43*x^4 +1)). - _Colin Barker_, Dec 18 2013

%t Denominator[Convergents[Sqrt[820], 30]] (* _Vincenzo Librandi_, Jan 25 2014 *)

%Y Cf. A042582, A040791.

%K nonn,frac,easy

%O 0,3

%A _N. J. A. Sloane_.

%E More terms from _Colin Barker_, Dec 18 2013