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A042265 Denominators of continued fraction convergents to sqrt(658). 2
1, 1, 2, 3, 20, 23, 43, 66, 3343, 3409, 6752, 10161, 67718, 77879, 145597, 223476, 11319397, 11542873, 22862270, 34405143, 229293128, 263698271, 492991399, 756689670, 38327474899, 39084164569, 77411639468, 116495804037, 776386463690, 892882267727 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index to sequences with linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,3386,0,0,0,0,0,0,0,-1).

FORMULA

G.f.: -(x^2-x-1)*(x^4+3*x^2+1)*(x^8+22*x^4+1) / (x^16-3386*x^8+1). - Colin Barker, Dec 06 2013

a(n) = 3386*a(n-8) - a(n-16) for n>15. - Vincenzo Librandi, Jan 19 2014

MAPLE

convert(sqrt(658), confrac, 30, cvgts): denom(cvgts); # Wesley Ivan Hurt, Dec 07 2013

MATHEMATICA

Denominator[Convergents[Sqrt[658], 30]] (* Vincenzo Librandi, Jan 19 2014 *)

PROG

(MAGMA) I:=[1, 1, 2, 3, 20, 23, 43, 66, 3343, 3409, 6752, 10161, 67718, 77879, 145597, 223476]; [n le 16 select I[n] else 3386*Self(n-8)-Self(n-16): n in [1..40]]; // Vincenzo Librandi, Jan 19 2014

CROSSREFS

Cf. A042264, A040632.

Sequence in context: A224987 A024630 A032809 * A041093 A154746 A042781

Adjacent sequences:  A042262 A042263 A042264 * A042266 A042267 A042268

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 06 2013

STATUS

approved

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Last modified September 22 00:15 EDT 2014. Contains 247035 sequences.