A042109 Denominators of continued fraction convergents to sqrt(579).

1, 16, 769, 12320, 592129, 9486384, 455938561, 7304503360, 351072099841, 5624458100816, 270325060939009, 4330825433124960, 208149945850937089, 3334729959048118384, 160275187980160619521, 2567737737641618030720, 123411686594777826094081

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (0, 770, 0, -1).

Formula

G.f.: -(x^2-16*x-1) / (x^4-770*x^2+1). - Colin Barker, Dec 02 2013

a/n) = 770*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Jan 14 2014

Mathematica

Denominator[Convergents[Sqrt[579], 30]] (* Vincenzo Librandi, Jan 14 2014 *)

Prog

(Magma) I:=[1, 16, 769, 12320]; [n le 4 select I[n] else 770*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jan 14 2014

Crossrefs

Cf. A042108, A040554.

Sequence in context: A221527 A129008 A134183 * A221061 A326216 A194610

Adjacent sequences: A042106 A042107 A042108 * A042110 A042111 A042112

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

Additional term from Colin Barker, Dec 02 2013

Status

approved