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A042351 Denominators of continued fraction convergents to sqrt(702). 2
1, 2, 105, 212, 11129, 22470, 1179569, 2381608, 125023185, 252427978, 13251278041, 26754984060, 1404510449161, 2835775882382, 148864856333025, 300565488548432, 15778270260851489, 31857106010251410, 1672347782793924809, 3376552671598101028 (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 (0,106,0,-1).

FORMULA

G.f.: -(x^2-2*x-1) / (x^4-106*x^2+1). - Colin Barker, Dec 09 2013

a(n) = 106*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Jan 20 2014

MATHEMATICA

Denominator[Convergents[Sqrt[702], 30]] (* Vincenzo Librandi, Jan 20 2014 *)

LinearRecurrence[{0, 106, 0, -1}, {1, 2, 105, 212}, 20] (* Harvey P. Dale, Apr 19 2020 *)

PROG

(MAGMA) I:=[1, 2, 105, 212]; [n le 4 select I[n] else 106*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jan 20 2014

CROSSREFS

Cf. A042350, A040675.

Sequence in context: A098653 A119433 A307227 * A258828 A156880 A280095

Adjacent sequences:  A042348 A042349 A042350 * A042352 A042353 A042354

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

Additional term from Colin Barker, Dec 09 2013

STATUS

approved

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Last modified May 11 18:16 EDT 2021. Contains 343805 sequences. (Running on oeis4.)