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%I #18 Sep 08 2022 08:44:55
%S 30,31,929,960,58529,59489,1783710,1843199,112375650,114218849,
%T 3424722271,3538941120,215761189471,219300130591,6575464976610,
%U 6794765107201,414261371408670,421056136515871,12624889330368929,13045945466884800,795381617343456929,808427562810341729
%N Numerators of continued fraction convergents to sqrt(959).
%H Vincenzo Librandi, <a href="/A042856/b042856.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 1920, 0, 0, 0, -1).
%F G.f.: (30 + 31*x + 929*x^2 + 960*x^3 + 929*x^4 - 31*x^5 + 30*x^6 - x^7)/(1 - 1920*x^4 + x^8). - _Vincenzo Librandi_, Dec 07 2013
%F a(n) = 1920*a(n-4) - a(n-8). - _Vincenzo Librandi_, Dec 07 2013
%t Numerator[Convergents[Sqrt[959], 30]] (* or *) CoefficientList[Series[(30 + 31 x + 929 x^2 + 960 x^3 + 929 x^4 - 31 x^5 + 30 x^6 - x^7)/(1 - 1920 x^4 + x^8),{x, 0, 30}], x] (* _Vincenzo Librandi_, Dec 07 2013 *)
%t LinearRecurrence[{0,0,0,1920,0,0,0,-1},{30,31,929,960,58529,59489,1783710,1843199},30] (* _Harvey P. Dale_, Apr 09 2015 *)
%o (Magma) I:=[ 30, 31, 929, 960, 58529, 59489, 1783710, 1843199 ]; [n le 8 select I[n] else 1920*Self(n-4)-Self(n-8): n in [1..30]]; // _Vincenzo Librandi_, Dec 07 2013
%Y Cf. A042857.
%K nonn,cofr,frac,easy
%O 0,1
%A _N. J. A. Sloane_.
%E More terms from _Vincenzo Librandi_, Dec 07 2013
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