A042271 Denominators of continued fraction convergents to sqrt(661).

1, 1, 3, 7, 31, 131, 2127, 2258, 22449, 47156, 69605, 882416, 4481685, 5364101, 9845786, 15209887, 40265560, 55475447, 206691901, 262167348, 468859249, 1668745095, 2137604344, 5943953783, 8081558127, 14025511910, 22107070037, 124560862095, 1516837415177

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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5730908870845166436, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

Formula

a(n) = 5730908870845166436*a(n-39) + a(n-78) for n>77. - Vincenzo Librandi, Jan 19 2014

Mathematica

Denominator[Convergents[Sqrt[661], 30]] (* Vincenzo Librandi, Jan 19 2014 *)

Crossrefs

Cf. A042270.

Sequence in context: A084732 A123488 A121620 * A000644 A015459 A115083

Adjacent sequences: A042268 A042269 A042270 * A042272 A042273 A042274

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Vincenzo Librandi, Jan 19 2014

Status

approved