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A042291 Denominators of continued fraction convergents to sqrt(671). 2
1, 1, 10, 21, 31, 52, 83, 218, 2045, 2263, 115195, 117458, 1172317, 2462092, 3634409, 6096501, 9730910, 25558321, 239755799, 265314120, 13505461799, 13770775919, 137442445070, 288655666059, 426098111129, 714753777188, 1140851888317, 2996457553822 (list; graph; refs; listen; history; text; internal format)
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, 117240, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

FORMULA

G.f.: -(x^18 -x^17 +10*x^16 -21*x^15 +31*x^14 -52*x^13 +83*x^12 -218*x^11 +2045*x^10 -2263*x^9 -2045*x^8 -218*x^7 -83*x^6 -52*x^5 -31*x^4 -21*x^3 -10*x^2 -x -1) / (x^20 -117240*x^10 +1). - Colin Barker, Dec 07 2013

MATHEMATICA

Denominator[Convergents[Sqrt[671], 30]] (* Vincenzo Librandi, Jan 19 2014 *)

CROSSREFS

Cf. A042290, A040645.

Sequence in context: A256825 A190326 A185691 * A041194 A042871 A041192

Adjacent sequences:  A042288 A042289 A042290 * A042292 A042293 A042294

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 07 2013

STATUS

approved

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Last modified April 21 10:58 EDT 2021. Contains 343150 sequences. (Running on oeis4.)