A041429 Denominators of continued fraction convergents to sqrt(230).

1, 6, 181, 1092, 32941, 198738, 5995081, 36169224, 1091071801, 6582600030, 198569072701, 1197997036236, 36138480159781, 218028877994922, 6577004820007441, 39680057798039568, 1196978738761194481, 7221552490365206454, 217843553449717388101

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, 182, 0, -1).

Formula

G.f.: -(x^2-6*x-1) / (x^4-182*x^2+1). - Colin Barker, Nov 17 2013

a(n) = 182*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 17 2013

Mathematica

Denominator[Convergents[Sqrt[230], 30]] (* Vincenzo Librandi, Dec 17 2013 *)

Prog

(Magma) I:=[1, 6, 181, 1092]; [n le 4 select I[n] else 182*Self(n-2)-Self(n-4): n in [1..100]]; // Vincenzo Librandi, Dec 17 2013

Crossrefs

Cf. A041428, A040214, A176909.

Sequence in context: A051357 A251671 A064120 * A089905 A222887 A012208

Adjacent sequences: A041426 A041427 A041428 * A041430 A041431 A041432

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Nov 17 2013

Status

approved