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A042209 Denominators of continued fraction convergents to sqrt(630). 2
1, 10, 501, 5020, 251501, 2520030, 126253001, 1265050040, 63378755001, 635052600050, 31816008757501, 318795140175060, 15971573017510501, 160034525315280070, 8017697838781514001, 80337012913130420080, 4024868343495302518001, 40329020447866155600090 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

Index to sequences with linear recurrences with constant coefficients, signature (0,502,0,-1).

FORMULA

G.f.: -(x^2-10*x-1) / (x^4-502*x^2+1). - Colin Barker, Dec 04 2013

MATHEMATICA

Denominator[Convergents[Sqrt[630], 30]] (* Vincenzo Librandi, Jan 16 2014_ *)

CROSSREFS

Cf. A042208, A040604.

Sequence in context: A039835 A127947 A095232 * A163703 A218720 A180476

Adjacent sequences:  A042206 A042207 A042208 * A042210 A042211 A042212

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 04 2013

STATUS

approved

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Last modified December 17 21:13 EST 2014. Contains 252040 sequences.