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A042622 Numerators of continued fraction convergents to sqrt(840). 2
28, 29, 1652, 1681, 95788, 97469, 5554052, 5651521, 322039228, 327690749, 18672721172, 19000411921, 1082695788748, 1101696200669, 62777683026212, 63879379226881, 3640022919731548, 3703902298958429 (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, 58, 0, -1).

FORMULA

G.f.: (28 +29*x +28*x^2 -x^3)/(1 -58*x^2 +x^4). - Vincenzo Librandi, Nov 29 2013

a(n) = 58*a(n-2) - a(n-4), - Vincenzo Librandi, Nov 29 2013

MATHEMATICA

Numerator[Convergents[Sqrt[840], 30]] (* or *) CoefficientList[Series[(28 + 29 x + 28 x^2 - x^3)/(1 - 58 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 29 2013 *)

LinearRecurrence[{0, 58, 0, -1}, {28, 29, 1652, 1681}, 30] (* Harvey P. Dale, Oct 03 2014 *)

PROG

(MAGMA) I:=[28, 29, 1652, 1681]; [n le 4 select I[n] else 58*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Nov 29 2013

CROSSREFS

Cf. A042623.

Sequence in context: A042618 A042620 A042621 * A044977 A046466 A054396

Adjacent sequences:  A042619 A042620 A042621 * A042623 A042624 A042625

KEYWORD

nonn,cofr,frac,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified November 12 14:43 EST 2019. Contains 329058 sequences. (Running on oeis4.)