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A042509 Denominators of continued fraction convergents to sqrt(782). 2
1, 1, 27, 28, 1539, 1567, 42281, 43848, 2410073, 2453921, 66212019, 68665940, 3774172779, 3842838719, 103687979473, 107530818192, 5910352161841, 6017882980033, 162375309642699, 168393192622732, 9255607711270227, 9424000903892959, 254279631212487161 (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 (0,0,0,1566,0,0,0,-1).

FORMULA

G.f.: -(x^2-x-1)*(x^4+28*x^2+1) / (x^8-1566*x^4+1). - Colin Barker, Dec 16 2013

a(0)=1, a(1)=1, a(2)=27, a(3)=28, a(4)=1539, a(5)=1567, a(6)=42281, a(7)=43848, a(n)=1566*a(n-4)-a(n-8). - Harvey P. Dale, Jun 20 2015

MATHEMATICA

Denominator[Convergents[Sqrt[782], 30]] (* Vincenzo Librandi, Jan 23 2014 *)

LinearRecurrence[{0, 0, 0, 1566, 0, 0, 0, -1}, {1, 1, 27, 28, 1539, 1567, 42281, 43848}, 30] (* Harvey P. Dale, Jun 20 2015 *)

CROSSREFS

Cf. A042508, A040754.

Sequence in context: A042506 A041363 A042508 * A042510 A157251 A214832

Adjacent sequences:  A042506 A042507 A042508 * A042510 A042511 A042512

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 16 2013

STATUS

approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)