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%I #18 May 31 2023 12:47:58
%S 1,1,10,21,31,52,83,218,2045,2263,115195,117458,1172317,2462092,
%T 3634409,6096501,9730910,25558321,239755799,265314120,13505461799,
%U 13770775919,137442445070,288655666059,426098111129,714753777188,1140851888317,2996457553822
%N Denominators of continued fraction convergents to sqrt(671).
%H Vincenzo Librandi, <a href="/A042291/b042291.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_20">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 117240, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^18 -x^17 +10*x^16 -21*x^15 +31*x^14 -52*x^13 +83*x^12 -218*x^11 +2045*x^10 -2263*x^9 -2045*x^8 -218*x^7 -83*x^6 -52*x^5 -31*x^4 -21*x^3 -10*x^2 -x -1) / (x^20 -117240*x^10 +1). - _Colin Barker_, Dec 07 2013
%t Denominator[Convergents[Sqrt[671], 30]] (* _Vincenzo Librandi_, Jan 19 2014 *)
%t LinearRecurrence[{0,0,0,0,0,0,0,0,0,117240,0,0,0,0,0,0,0,0,0,-1},{1,1,10,21,31,52,83,218,2045,2263,115195,117458,1172317,2462092,3634409,6096501,9730910,25558321,239755799,265314120},30] (* _Harvey P. Dale_, May 31 2023 *)
%Y Cf. A042290, A040645.
%K nonn,frac,easy
%O 0,3
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Dec 07 2013