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%I #16 Mar 19 2017 12:41:48
%S 1,6,7,20,127,274,401,2680,161201,969886,1131087,3232060,20523447,
%T 44278954,64802401,433093360,26050404001,156735517366,182785921367,
%U 522307360100,3316630081967,7155567524034,10472197606001,69988753160040,4209797387208401
%N Denominators of continued fraction convergents to sqrt(909).
%H Vincenzo Librandi, <a href="/A042757/b042757.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 161602, 0, 0, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^14 -6*x^13 +7*x^12 -20*x^11 +127*x^10 -274*x^9 +401*x^8 -2680*x^7 -401*x^6 -274*x^5 -127*x^4 -20*x^3 -7*x^2 -6*x -1) / ((x^4 -20*x^2 -1)*(x^4 +20*x^2 -1)*(x^8 +402*x^4 +1)). - _Colin Barker_, Dec 23 2013
%t Denominator[Convergents[Sqrt[909], 30]] (* _Vincenzo Librandi_, Jan 28 2014 *)
%Y Cf. A042756, A040878.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Dec 23 2013