%I #16 Sep 08 2022 08:44:55
%S 22,485,21362,470449,20721118,456335045,20099463098,442644523201,
%T 19496458483942,429364731169925,18911544629960642,416483346590304049,
%U 18344178794603338798,403988416827863757605,17793834519220608673418
%N Numerators of continued fraction convergents to sqrt(486).
%H Vincenzo Librandi, <a href="/A041926/b041926.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 (0,970,0,-1).
%F G.f.: (22 + 485*x + 22*x^2 - x^3)/(1 - 970*x^2 + x^4). - _Vincenzo Librandi_, Nov 12 2013
%F a(n) = 970*a(n-2) - a(n-4). - _Vincenzo Librandi_, Nov 12 2013
%t Numerator[Convergents[Sqrt[486], 30]] (* or *) CoefficientList[Series[(22 + 485 x + 22 x^2 - x^3)/(1 - 970 x^2 + x^4), {x, 0, 30}], x] (* _Vincenzo Librandi_, Nov 12 2013 *)
%o (Magma) I:=[22,485,21362,470449]; [n le 4 select I[n] else 970*Self(n-2)-Self(n-4): n in [1..25]]; // _Vincenzo Librandi_, Nov 12 2013
%Y Cf. A041927.
%K nonn,cofr,frac,easy,less
%O 0,1
%A _N. J. A. Sloane_.
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