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A041241 Denominators of continued fraction convergents to sqrt(132). 2
1, 2, 45, 92, 2069, 4230, 95129, 194488, 4373865, 8942218, 201102661, 411147540, 9246348541, 18903844622, 425130930225, 869165705072, 19546776441809, 39962718588690, 898726585392989, 1837415889374668, 41321876151635685, 84481168192646038 (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 (0,46,0,-1).

FORMULA

G.f.: -(x^2-2*x-1) / (x^4-46*x^2+1). - Colin Barker, Nov 14 2013

a(n) = 46*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 13 2013

MATHEMATICA

Denominator[Convergents[Sqrt[132], 30]]  (* Vincenzo Librandi, Dec 13 2013 *)

PROG

(MAGMA) I:=[1, 2, 45, 92]; [n le 4 select I[n] else 46*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 13 2013

CROSSREFS

Cf. A041240, A040120.

Sequence in context: A321058 A264438 A241762 * A304015 A279680 A305363

Adjacent sequences:  A041238 A041239 A041240 * A041242 A041243 A041244

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 14 2013

STATUS

approved

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Last modified August 15 16:02 EDT 2020. Contains 336505 sequences. (Running on oeis4.)