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%I #19 Jul 18 2023 15:16:21
%S 1,2,3,5,18,41,223,933,4888,10709,37015,47724,84739,217202,12248051,
%T 24713304,36961355,61674659,221985332,505645323,2750211947,
%U 11506493111,60282677502,132071848115,456498221847,588570069962,1045068291809,2678706653580
%N Denominators of continued fraction convergents to sqrt(806).
%H Vincenzo Librandi, <a href="/A042555/b042555.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_28">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12332790, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).
%F a(n) = 12332790*a(n-14) - a(n-28) for n > 27. - _Vincenzo Librandi_, Jan 25 2014
%t Denominator[Convergents[Sqrt[806], 30]] (* _Vincenzo Librandi_, Jan 25 2014 *)
%t LinearRecurrence[{0,0,0,0,0,0,0,0,0,0,0,0,0,12332790,0,0,0,0,0,0,0,0,0,0,0,0,0,-1},{1,2,3,5,18,41,223,933,4888,10709,37015,47724,84739,217202,12248051,24713304,36961355,61674659,221985332,505645323,2750211947,11506493111,60282677502,132071848115,456498221847,588570069962,1045068291809,2678706653580},30] (* _Harvey P. Dale_, May 26 2018 *)
%o (PARI) vector(30, i, contfracpnqn(contfrac(sqrt(806), i))[2, 1]) \\ _Jinyuan Wang_, Feb 28 2020
%Y Cf. A040777, A042554.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_
%E More terms from _Vincenzo Librandi_, Jan 25 2014