A042415 Denominators of continued fraction convergents to sqrt(735).

1, 9, 487, 4392, 237655, 2143287, 115975153, 1045919664, 56595637009, 510406652745, 27618554885239, 249077400619896, 13477798188359623, 121549261095856503, 6577137897364610785, 59315790337377353568, 3209629816115741703457

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• frac
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..200
• Index entries for linear recurrences with constant coefficients, signature (0,488,0,-1).

Crossrefs

Cf. A042414, A040707.

Programs

Mathematica

Denominator[Convergents[Sqrt[735], 20]] (* Harvey P. Dale, Oct 11 2011 *)
CoefficientList[Series[(1 + 9 x - x^2)/(x^4 - 488 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Jan 21 2014 *)

Formula

G.f.: -(x^2-9*x-1) / (x^4-488*x^2+1). - Colin Barker, Dec 12 2013

Extensions

More terms from Colin Barker, Dec 12 2013