A042661 Denominators of continued fraction convergents to sqrt(860).

1, 3, 43, 132, 7699, 23229, 332905, 1021944, 59605657, 179838915, 2577350467, 7911890316, 461466988795, 1392312856701, 19953846982609, 61253853804528, 3572677367645233, 10779285956740227, 154482680762008411, 474227328242765460

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,7742,0,0,0,-1).

Formula

G.f.: -(x^2-3*x-1)*(x^4+44*x^2+1) / ((x^4-88*x^2+1)*(x^4+88*x^2+1)). - Colin Barker, Dec 20 2013

Mathematica

Denominator[Convergents[Sqrt[860], 30]] (* Vincenzo Librandi, Jan 26 2014 *)
LinearRecurrence[{0, 0, 0, 7742, 0, 0, 0, -1}, {1, 3, 43, 132, 7699, 23229, 332905, 1021944}, 40] (* Harvey P. Dale, May 11 2021 *)

Crossrefs

Cf. A042660, A040829.

Sequence in context: A127930 A062647 A003525 * A281503 A030990 A306970

Adjacent sequences: A042658 A042659 A042660 * A042662 A042663 A042664

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Dec 20 2013

Status

approved