A042279 Denominators of continued fraction convergents to sqrt(665).

1, 1, 4, 5, 14, 33, 80, 113, 419, 532, 27019, 27551, 109672, 137223, 384118, 905459, 2195036, 3100495, 11496521, 14597016, 741347321, 755944337, 3009180332, 3765124669, 10539429670, 24843984009, 60227397688, 85071381697, 315441542779, 400512924476

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, 27438, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

Formula

G.f.: -(x^18 -x^17 +4*x^16 -5*x^15 +14*x^14 -33*x^13 +80*x^12 -113*x^11 +419*x^10 -532*x^9 -419*x^8 -113*x^7 -80*x^6 -33*x^5 -14*x^4 -5*x^3 -4*x^2 -x -1) / (x^20 -27438*x^10 +1). - Colin Barker, Dec 06 2013

Maple

convert(sqrt(665), confrac, 30, cvgts): denom(cvgts); # Wesley Ivan Hurt, Dec 07 2013

Mathematica

Denominator[Convergents[Sqrt[665], 30]] (* Vincenzo Librandi, Jan 19 2014 *)

Crossrefs

Cf. A042278, A040639.

Sequence in context: A216243 A093862 A041375 * A352683 A182252 A041857

Adjacent sequences: A042276 A042277 A042278 * A042280 A042281 A042282

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Dec 06 2013

Status

approved