A042387 Denominators of continued fraction convergents to sqrt(720).

1, 1, 5, 6, 317, 323, 1609, 1932, 102073, 104005, 518093, 622098, 32867189, 33489287, 166824337, 200313624, 10583132785, 10783446409, 53716918421, 64500364830, 3407735889581, 3472236254411, 17296680907225

Offset

0,3

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,322,0,0,0,-1).

Formula

G.f.: -(x^2-x-1)*(x^4+6*x^2+1)/((x^2-4*x-1)*(x^2+4*x-1)*(x^4+18*x^2+1)). [Colin Barker, Aug 09 2012]

Mathematica

Denominator[Convergents[Sqrt[720], 30]] (* Vincenzo Librandi, Oct 25 2013 *)

Crossrefs

Cf. A042386.

Sequence in context: A041827 A042089 A156191 * A007666 A064177 A042721

Adjacent sequences: A042384 A042385 A042386 * A042388 A042389 A042390

Keyword

nonn,cofr,frac,easy

Author

N. J. A. Sloane.

Status

approved