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A042108 Numerators of continued fraction convergents to sqrt(579). 2
24, 385, 18504, 296449, 14248056, 228265345, 10970984616, 175764019201, 8447643906264, 135338066519425, 6504674836838664, 104210135455938049, 5008591176721865016, 80241668963005778305, 3856608701400999223656 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0, 770, 0, -1).

FORMULA

G.f.: (24 + 385*x + 24*x^2 - x^3)/(1 - 770*x^2 + x^4). - Vincenzo Librandi, Nov 16 2013

a(n) = 770*a(n-2) - a(n-4). - Vincenzo Librandi, Nov 16 2013

MATHEMATICA

Numerator[Convergents[Sqrt[579], 30]] (* or *) CoefficientList[Series[(24 + 385 x + 24 x^2 - x^3)/(1 - 770 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 16 2013 *)

LinearRecurrence[{0, 770, 0, -1}, {24, 385, 18504, 296449}, 20] (* Harvey P. Dale, Nov 06 2021 *)

PROG

(MAGMA) I:=[24, 385, 18504, 296449]; [n le 4 select I[n] else 770*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Nov 16 2013

CROSSREFS

Cf. A042109.

Sequence in context: A020782 A025952 A028031 * A022455 A021954 A025950

Adjacent sequences:  A042105 A042106 A042107 * A042109 A042110 A042111

KEYWORD

nonn,cofr,frac,easy,less

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified December 9 03:23 EST 2021. Contains 349625 sequences. (Running on oeis4.)