A041916 Numerators of continued fraction convergents to sqrt(480).

21, 22, 219, 241, 10341, 10582, 105579, 116161, 4984341, 5100502, 50888859, 55989361, 2402442021, 2458431382, 24528324459, 26986755841, 1157972069781, 1184958825622, 11822601500379, 13007560326001

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0,0,0,482,0,0,0,-1).

Formula

a(n) = 482*a(n-4)-a(n-8). G.f.: -(x^7-21*x^6+22*x^5-219*x^4-241*x^3-219*x^2-22*x-21)/((x^4-22*x^2+1)*(x^4+22*x^2+1)). [Colin Barker, Jul 16 2012]

Mathematica

Numerator[Convergents[Sqrt[480], 30]] (* Harvey P. Dale, Aug 14 2012 *)
CoefficientList[Series[- (x^7 - 21 x^6 + 22 x^5 - 219 x^4 - 241 x^3 - 219 x^2 - 22 x - 21)/((x^4 - 22 x^2 + 1) (x^4 + 22 x^2 + 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Oct 27 2013 *)

Crossrefs

Cf. A041917.

Sequence in context: A041910 A041912 A041914 * A041918 A068325 A041219

Adjacent sequences: A041913 A041914 A041915 * A041917 A041918 A041919

Keyword

nonn,cofr,easy,frac,less

Author

N. J. A. Sloane.

Status

approved