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A041487 Denominators of continued fraction convergents to sqrt(260). 2
1, 8, 257, 2064, 66305, 532504, 17106433, 137383968, 4413393409, 35444531240, 1138638393089, 9144551675952, 293764292023553, 2359258887864376, 75790048703683585, 608679648517333056, 19553538801258341377, 157036990058584064072, 5044737220675948391681 (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 (0,258,0,-1).

FORMULA

G.f.: -(x^2-8*x-1) / ((x^2-16*x-1)*(x^2+16*x-1)). - Colin Barker, Nov 18 2013

a(n) = 258*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Dec 18 2013

MATHEMATICA

Denominator[Convergents[Sqrt[260], 30]] (* Vincenzo Librandi, Dec 18 2013 *)

PROG

(Magma) I:=[1, 8, 257, 2064]; [n le 4 select I[n] else 258*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Dec 18 2013

CROSSREFS

Cf. A041486, A040243.

Sequence in context: A140339 A103488 A341479 * A034988 A230271 A221778

Adjacent sequences:  A041484 A041485 A041486 * A041488 A041489 A041490

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 September 29 03:50 EDT 2022. Contains 357082 sequences. (Running on oeis4.)