%I #18 Sep 08 2022 08:44:54
%S 1,12,289,3480,83809,1009188,24304321,292661040,7048169281,
%T 84870692412,2043944787169,24612208138440,592736940109729,
%U 7137455489455188,171891668687034241,2069837479733866080,49847991182299820161,600245731667331708012
%N Denominators of continued fraction convergents to sqrt(146).
%H Vincenzo Librandi, <a href="/A041267/b041267.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 (0,290,0,-1).
%F G.f.: (1 +12*x -x^2)/(x^4 -290*x^2 +1). - _Vincenzo Librandi_, Dec 14 2013
%F a(n) = 290*a(n-2) - a(n-4). - _Vincenzo Librandi_, Dec 14 2013
%t Denominator[Convergents[Sqrt[146], 30]] (* or *) CoefficientList[Series[(1 + 12 x - x^2)/(x^4 - 290 x^2 + 1), {x, 0, 30}], x] (* _Vincenzo Librandi_, Dec 14 2013 *)
%t LinearRecurrence[{0,290,0,-1},{1,12,289,3480},20] (* _Harvey P. Dale_, Jan 20 2021 *)
%o (Magma) I:=[1,12,289,3480]; [n le 4 select I[n] else 290*Self(n-2)-Self(n-4): n in [1..40]]; // _Vincenzo Librandi_, Dec 14 2013
%Y Cf. A041266.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Vincenzo Librandi_, Dec 14 2013