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%I #17 Sep 08 2022 08:44:54
%S 1,2,13,28,965,1958,12713,27384,943769,1914922,12433301,26781524,
%T 923005117,1872791758,12159755665,26192303088,902698060657,
%U 1831588424402,11892228607069,25616045638540,882837780317429,1791291606273398,11630587417957817,25052466442189032
%N Denominators of continued fraction convergents to sqrt(305).
%H Vincenzo Librandi, <a href="/A041575/b041575.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 (0,0,0,978,0,0,0,-1).
%F G.f.: -(x^2-2*x-1)*(x^4+14*x^2+1) / (x^8-978*x^4+1). - _Colin Barker_, Nov 19 2013
%F a(n) = 978*a(n-4) - a(n-8) for n>7. - _Vincenzo Librandi_, Dec 20 2013
%t Denominator[Convergents[Sqrt[305], 30]] (* _Vincenzo Librandi_, Dec 20 2013 *)
%t LinearRecurrence[{0,0,0,978,0,0,0,-1},{1,2,13,28,965,1958,12713,27384},30] (* _Harvey P. Dale_, Nov 03 2015 *)
%o (Magma) I:=[1,2,13,28,965,1958,12713,27384]; [n le 8 select I[n] else 978*Self(n-4)-Self(n-8): n in [1..40]]; // _Vincenzo Librandi_, Dec 20 2013
%Y Cf. A041574, A040287.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Nov 19 2013
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