A041821 Denominators of continued fraction convergents to sqrt(431).

1, 1, 4, 21, 25, 71, 522, 593, 11789, 12382, 98463, 209308, 307771, 1748163, 5552260, 7300423, 297569180, 304869603, 1212177989, 6365759548, 7577937537, 21521634622, 158229379891, 179751014513, 3573498655638, 3753249670151, 29846246346695, 63445742363541

Offset

0,3

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,303121440,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-1).

Formula

a(n) = 303121440*a(n-16)- a(n-32) for n>31. - Vincenzo Librandi, Dec 25 2013

Mathematica

Denominator[Convergents[Sqrt[431], 50]] (* Harvey P. Dale, Jun 04 2012 *)

Crossrefs

Cf. A041820.

Sequence in context: A305225 A272954 A133784 * A042429 A356357 A276400

Adjacent sequences: A041818 A041819 A041820 * A041822 A041823 A041824

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Vincenzo Librandi, Dec 25 2013

Status

approved