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A041523 Denominators of continued fraction convergents to sqrt(278). 2
1, 1, 3, 49, 101, 150, 4901, 5051, 15003, 245099, 505201, 750300, 24514801, 25265101, 75045003, 1225985149, 2527015301, 3753000450, 122623029701, 126376030151, 375375090003, 6132377470199, 12640130030401, 18772507500600, 613360370049601, 632132877550201 (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 (0,0,0,0,0,5002,0,0,0,0,0,-1).

FORMULA

G.f.: -(x^10-x^9+3*x^8-49*x^7+101*x^6-150*x^5-101*x^4-49*x^3-3*x^2-x-1) / (x^12-5002*x^6+1). - Colin Barker, Nov 18 2013

a(n) = 5002*a(n-6) - a(n-12) for n>11. - Vincenzo Librandi, Dec 19 2013

MATHEMATICA

Denominator/@Convergents[Sqrt[278], 50]  (* Harvey P. Dale, Mar 13 2011 *)

CoefficientList[Series[-(x^10 - x^9 + 3 x^8 - 49 x^7 + 101 x^6 - 150 x^5 - 101 x^4 - 49 x^3 - 3 x^2 - x - 1)/(x^12 - 5002 x^6 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 19 2013 *)

PROG

(MAGMA) I:=[1, 1, 3, 49, 101, 150, 4901, 5051, 15003, 245099, 505201, 750300]; [n le 12 select I[n] else 5002*Self(n-6)-Self(n-12): n in [1..40]]; // Vincenzo Librandi, Dec 19 2013

CROSSREFS

Cf. A041522, A040261.

Sequence in context: A188380 A252171 A160763 * A054206 A063777 A212651

Adjacent sequences:  A041520 A041521 A041522 * A041524 A041525 A041526

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 18 2013

STATUS

approved

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Last modified February 15 20:07 EST 2019. Contains 320138 sequences. (Running on oeis4.)