A041049 Denominators of continued fraction convergents to sqrt(30).

1, 2, 21, 44, 461, 966, 10121, 21208, 222201, 465610, 4878301, 10222212, 107100421, 224423054, 2351330961, 4927084976, 51622180721, 108171446418, 1133336644901, 2374844736220, 24881784007101

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,22,0,-1).

Formula

G.f.: (1+2*x-x^2)/(1-22*x^2+x^4). [Colin Barker, Jan 02 2012]

Mathematica

Table[Denominator[FromContinuedFraction[ContinuedFraction[Sqrt[30], n]]], {n, 1, 50}] (* Vladimir Joseph Stephan Orlovsky, Mar 18 2011 *)
Denominator[Convergents[Sqrt[30], 20]] (* Vincenzo Librandi, Oct 23 2013 *)

Crossrefs

Cf. A010485, A040024, A041048 (numerators).

Sequence in context: A089558 A266873 A215753 * A224346 A005484 A330201

Adjacent sequences: A041046 A041047 A041048 * A041050 A041051 A041052

Keyword

nonn,cofr,frac,easy

Author

N. J. A. Sloane

Status

approved