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A041351 Denominators of continued fraction convergents to sqrt(189). 2
1, 1, 3, 4, 107, 111, 329, 440, 11769, 12209, 36187, 48396, 1294483, 1342879, 3980241, 5323120, 142381361, 147704481, 437790323, 585494804, 15660655227, 16246150031, 48152955289, 64399105320, 1722529693609, 1786928798929, 5296387291467, 7083316090396 (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 (0,0,0,110,0,0,0,-1).

FORMULA

G.f.: -(x^2-x-1)*(x^4+4*x^2+1) / (x^8-110*x^4+1). - Colin Barker, Nov 16 2013

a(n) = 110*a(n-4) - a(n-8). - Vincenzo Librandi, Dec 16 2013

MATHEMATICA

Denominator[Convergents[Sqrt[189], 30]] (* Vincenzo Librandi, Dec 16 2013 *)

PROG

(MAGMA) I:=[1, 1, 3, 4, 107, 111, 329, 440]; [n le 8 select I[n] else 110*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Dec 16 2013

CROSSREFS

Cf. A041350, A010231.

Sequence in context: A297119 A156182 A126578 * A266516 A066496 A041465

Adjacent sequences:  A041348 A041349 A041350 * A041352 A041353 A041354

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 16 2013

STATUS

approved

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Last modified February 21 03:02 EST 2020. Contains 332086 sequences. (Running on oeis4.)