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Denominators of continued fraction convergents to sqrt(480).
3

%I #18 Jun 13 2015 00:49:38

%S 1,1,10,11,472,483,4819,5302,227503,232805,2322748,2555553,109655974,

%T 112211527,1119559717,1231771244,52853951965,54085723209,539625460846,

%U 593711184055,25475495191156,26069206375211,260098352568055,286167558943266,12279135828185227

%N Denominators of continued fraction convergents to sqrt(480).

%H Vincenzo Librandi, <a href="/A041917/b041917.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 (0,0,0,482,0,0,0,-1).

%F a(n) = 482*a(n-4)-a(n-8). G.f.: -(x^2-x-1)*(x^4+11*x^2+1)/((x^4-22*x^2+1)*(x^4+22*x^2+1)). [_Colin Barker_, Jul 16 2012]

%t Table[Denominator[FromContinuedFraction[ContinuedFraction[Sqrt[480], n]]], {n, 1, 50}] (* _Vladimir Joseph Stephan Orlovsky_, Jun 23 2011 *)

%t Denominator[Convergents[Sqrt[480], 30]] (* _Vincenzo Librandi_, Oct 25 2013 *)

%Y Cf. A041916.

%K nonn,cofr,frac,easy

%O 0,3

%A _N. J. A. Sloane_.