A041743 Denominators of continued fraction convergents to sqrt(391).

1, 1, 4, 9, 22, 31, 53, 137, 2656, 5449, 8105, 13554, 35213, 83980, 287153, 371133, 14390207, 14761340, 58674227, 132109794, 322893815, 455003609, 777897424, 2010798457, 38983068107, 79976934671, 118960002778, 198936937449, 516833877676, 1232604692801

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, 14677360, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

Formula

a(n) = 14677360*a(n-16) - a(n-32) for n>31. - Vincenzo Librandi, Dec 23 2013

Mathematica

Denominator[Convergents[Sqrt[391], 30]] (* Vincenzo Librandi, Dec 23 2013 *)

Crossrefs

Cf. A041742.

Sequence in context: A374943 A048391 A343322 * A041943 A158140 A290647

Adjacent sequences: A041740 A041741 A041742 * A041744 A041745 A041746

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Vincenzo Librandi, Dec 23 2013

Status

approved