A041919 Denominators of continued fraction convergents to sqrt(481).

1, 1, 14, 15, 29, 44, 205, 864, 1069, 1933, 3002, 40959, 43961, 1887321, 1931282, 26993987, 28925269, 55919256, 84844525, 395297356, 1666033949, 2061331305, 3727365254, 5788696559, 78980420521, 84769117080, 3639283337881, 3724052454961, 52051965252374

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, 1928280, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

Formula

a(n) = 1928280*a(n-13) + a(n-26) for n>25. - Vincenzo Librandi, Dec 27 2013

Mathematica

Denominator[Convergents[Sqrt[481], 40]] (* Harvey P. Dale, Mar 31 2012 *)

Prog

(Magma) I:=[1, 1, 14, 15, 29, 44, 205, 864, 1069, 1933, 3002, 40959, 43961, 1887321, 1931282, 26993987, 28925269, 55919256, 84844525, 395297356, 1666033949, 2061331305, 3727365254, 5788696559, 78980420521, 84769117080]; [n le 26 select I[n] else 1928280*Self(n-13)+Self(n-26): n in [1..40]]; // Vincenzo Librandi, Dec 27 2013

Crossrefs

Cf. A041918.

Sequence in context: A075659 A022104 A041398 * A041400 A041396 A041394

Adjacent sequences: A041916 A041917 A041918 * A041920 A041921 A041922

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Vincenzo Librandi, Dec 27 2013

Status

approved