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%I #21 Jan 30 2023 18:09:42
%S 1,1,5,56,229,285,12769,13054,64985,727889,2976541,3704430,165971461,
%T 169675891,844675025,9461101166,38689079689,48150180855,2157297037309,
%U 2205447218164,10979085909965,122975392227779,502880654821081,625856047048860
%N Denominators of continued fraction convergents to sqrt(520).
%H Vincenzo Librandi, <a href="/A041995/b041995.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 12998, 0, 0, 0, 0, 0, -1).
%F G.f.: -(x^10 -x^9 +5*x^8 -56*x^7 +229*x^6 -285*x^5 -229*x^4 -56*x^3 -5*x^2 -x -1) / ((x^6 -114*x^3 -1)*(x^6 +114*x^3 -1)). - _Colin Barker_, Nov 28 2013
%F a(n) = 12998*a(n-6) - a(n-12) for n>11. - _Vincenzo Librandi_, Jan 12 2014
%t Denominator[Convergents[Sqrt[520], 40]] (* _Vincenzo Librandi_, Jan 12 2014 *)
%t LinearRecurrence[{0,0,0,0,0,12998,0,0,0,0,0,-1},{1,1,5,56,229,285,12769,13054,64985,727889,2976541,3704430},30] (* _Harvey P. Dale_, Jan 30 2023 *)
%o (Magma) I:=[1,1,5,56,229,285,12769,13054,64985,727889, 2976541,3704430]; [n le 12 select I[n] else 12998*Self(n-6)-Self(n-12): n in [1..30]]; // _Vincenzo Librandi_, Jan 12 2014
%Y Cf. A041994, A040497.
%K nonn,frac,easy
%O 0,3
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Nov 28 2013
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