A041807 Denominators of continued fraction convergents to sqrt(424).

1, 1, 2, 5, 22, 115, 137, 252, 389, 3753, 4142, 7895, 12037, 68080, 284357, 636794, 921151, 1557945, 63238951, 64796896, 128035847, 320868590, 1411510207, 7378419625, 8789929832, 16168349457, 24958279289, 240792863058, 265751142347, 506544005405

Offset

0,3

Links

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

Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 64160102, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

Formula

a(n) = 64160102*a(n-18) - a(n-36) for n>35. - Vincenzo Librandi, Dec 24 2013

Mathematica

Denominator[Convergents[Sqrt[424], 30]] (* Vincenzo Librandi, Dec 24 2013 *)

Crossrefs

Cf. A041806.

Sequence in context: A381787 A294467 A177251 * A228711 A215096 A115602

Adjacent sequences: A041804 A041805 A041806 * A041808 A041809 A041810

Keyword

nonn,frac,easy

Author

N. J. A. Sloane

Extensions

More terms from Vincenzo Librandi, Dec 24 2013

Status

approved