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A041267 Denominators of continued fraction convergents to sqrt(146). 2
1, 12, 289, 3480, 83809, 1009188, 24304321, 292661040, 7048169281, 84870692412, 2043944787169, 24612208138440, 592736940109729, 7137455489455188, 171891668687034241, 2069837479733866080, 49847991182299820161, 600245731667331708012 (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 (0,290,0,-1).

FORMULA

G.f.: (1 +12*x -x^2)/(x^4 -290*x^2 +1). - Vincenzo Librandi, Dec 14 2013

a(n) = 290*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 14 2013

MATHEMATICA

Denominator[Convergents[Sqrt[146], 30]] (* or *) CoefficientList[Series[(1 + 12 x - x^2)/(x^4 - 290 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 14 2013 *)

PROG

(MAGMA) I:=[1, 12, 289, 3480]; [n le 4 select I[n] else 290*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 14 2013

CROSSREFS

Cf. A041266.

Sequence in context: A145448 A001164 A226100 * A041264 A220307 A223011

Adjacent sequences:  A041264 A041265 A041266 * A041268 A041269 A041270

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Vincenzo Librandi, Dec 14 2013

STATUS

approved

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Last modified December 5 15:24 EST 2016. Contains 278770 sequences.