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A041953 Denominators of continued fraction convergents to sqrt(499). 2
1, 2, 3, 65, 68, 201, 8912, 18025, 26937, 583702, 610639, 1804980, 80029759, 161864498, 241894257, 5241643895, 5483538152, 16208720199, 718667226908, 1453543174015, 2172210400923, 47069961593398, 49242171994321, 145554305582040, 6453631617604081 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

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, 8980, 0, 0, 0, 0, 0, -1).

FORMULA

G.f.: -(x^10-2*x^9+3*x^8-65*x^7+68*x^6-201*x^5-68*x^4-65*x^3-3*x^2-2*x-1) / (x^12-8980*x^6+1). - Colin Barker, Nov 28 2013

a(n) = 8980*a(n-6) - a(n-12) for n>11. - Vincenzo Librandi, Dec 27 2013

MATHEMATICA

Denominator[Convergents[Sqrt[499], 30]] (* Vincenzo Librandi, Dec 27 2013 *)

PROG

(MAGMA) I:=[1, 2, 3, 65, 68, 201, 8912, 18025, 26937, 583702, 610639, 1804980]; [n le 12 select I[n] else 8980*Self(n-6)-Self(n-12): n in [1..40]]; // Vincenzo Librandi, Dec 27 2013

CROSSREFS

Cf. A041952, A040476.

Sequence in context: A037426 A004854 A015169 * A099080 A132532 A108023

Adjacent sequences:  A041950 A041951 A041952 * A041954 A041955 A041956

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 28 2013

STATUS

approved

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Last modified January 23 06:38 EST 2022. Contains 350504 sequences. (Running on oeis4.)