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A042285 Denominators of continued fraction convergents to sqrt(668). 2
1, 1, 6, 13, 162, 337, 1847, 2184, 111047, 113231, 677202, 1467635, 18288822, 38045279, 208515217, 246560496, 12536540017, 12783100513, 76452042582, 165687185677, 2064698270706, 4295083727089, 23540116906151, 27835200633240, 1415300148568151 (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 (0,0,0,0,0,0,0,112894,0,0,0,0,0,0,0,-1).

FORMULA

G.f.: -(x^14 -x^13 +6*x^12 -13*x^11 +162*x^10 -337*x^9 +1847*x^8 -2184*x^7 -1847*x^6 -337*x^5 -162*x^4 -13*x^3 -6*x^2 -x -1) / ((x^8 -336*x^4 +1)*(x^8 +336*x^4 +1)). - Colin Barker, Dec 07 2013

MATHEMATICA

Denominator[Convergents[Sqrt[668], 30]] (* Vincenzo Librandi, Jan 19 2014 *)

CROSSREFS

Cf. A042284, A040642.

Sequence in context: A042641 A292121 A236250 * A041070 A248263 A201449

Adjacent sequences:  A042282 A042283 A042284 * A042286 A042287 A042288

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 December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)