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A042005 Denominators of continued fraction convergents to sqrt(525). 2
1, 1, 11, 23, 241, 264, 11857, 12121, 133067, 278255, 2915617, 3193872, 143445985, 146639857, 1609844555, 3366328967, 35273134225, 38639463192, 1735409514673, 1774048977865, 19475899293323, 40725847564511, 426734374938433, 467460222502944 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 12098, 0, 0, 0, 0, 0, -1).

FORMULA

G.f.: -(x^10 -x^9 +11*x^8 -23*x^7 +241*x^6 -264*x^5 -241*x^4 -23*x^3 -11*x^2 -x -1) / ((x^2 -5*x +1)*(x^2 +5*x +1)*(x^4 -5*x^3 +24*x^2 -5*x +1)*(x^4 +5*x^3 +24*x^2 +5*x +1)). - Colin Barker, Nov 28 2013

a(n) = 12098*a(n-6) - a(n-12) for n>11. - Vincenzo Librandi, Jan 12 2014

MATHEMATICA

Denominator[Convergents[Sqrt[525], 40]] (* Vincenzo Librandi, Jan 12 2014 *)

PROG

(MAGMA) I:=[1, 1, 11, 23, 241, 264, 11857, 12121, 133067, 278255, 2915617, 3193872]; [n le 12 select I[n] else 12098*Self(n-6)-Self(n-12): n in [1..30]]; // Vincenzo Librandi, Jan 12 2014

CROSSREFS

Cf. A042004, A040502.

Sequence in context: A018979 A181147 A059327 * A153318 A005485 A041240

Adjacent sequences:  A042002 A042003 A042004 * A042006 A042007 A042008

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 28 2013

STATUS

approved

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Last modified February 16 12:48 EST 2019. Contains 320163 sequences. (Running on oeis4.)