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A042438 Numerators of continued fraction convergents to sqrt(747). 2
27, 82, 4455, 13447, 730593, 2205226, 119812797, 361643617, 19648568115, 59307347962, 3222245358063, 9726043422151, 528428590154217, 1595011813884802, 86659066539933525, 261572211433685377 (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, 164, 0, -1).

FORMULA

G.f.: (27 + 82*x + 27*x^2 - x^3)/(1 - 164*x^2 + x^4), - Vincenzo Librandi, Nov 24 2013

a(n) = 164*a(n-2) - a(n-4). - Vincenzo Librandi, Nov 24 2013

MATHEMATICA

Numerator[Convergents[Sqrt[747], 30]] (* or *) CoefficientList[Series[(27 + 82 x + 27 x^2 - x^3)/(1 - 164 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 24 2013 *)

PROG

(Magma) I:=[27, 82, 4455, 13447]; [n le 4 select I[n] else 164*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Nov 24 2013

CROSSREFS

Cf. A042439.

Sequence in context: A195028 A042434 A042436 * A251088 A044981 A251081

Adjacent sequences:  A042435 A042436 A042437 * A042439 A042440 A042441

KEYWORD

nonn,cofr,frac,easy

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified September 26 12:54 EDT 2022. Contains 356998 sequences. (Running on oeis4.)