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A041909 Denominators of continued fraction convergents to sqrt(476). 2
1, 1, 5, 11, 115, 241, 1079, 1320, 56519, 57839, 287875, 633589, 6623765, 13881119, 62148241, 76029360, 3255381361, 3331410721, 16581024245, 36493459211, 381515616355, 799524691921, 3579614384039, 4379139075960, 187503455574359, 191882594650319 (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, 0, 0, 57598, 0, 0, 0, 0, 0, 0, 0, -1).

FORMULA

G.f.: -(x^14 -x^13 +5*x^12 -11*x^11 +115*x^10 -241*x^9 +1079*x^8 -1320*x^7 -1079*x^6 -241*x^5 -115*x^4 -11*x^3 -5*x^2 -x -1) / ((x^8 -240*x^4 +1)*(x^8 +240*x^4 +1)). - Colin Barker, Nov 27 2013

a(n) = 57598*a(n-8) - a(n-16) for n>15. - Vincenzo Librandi, Dec 27 2013

MATHEMATICA

Denominator[Convergents[Sqrt[476], 30]] (* Vincenzo Librandi, Dec 27 2013 *)

PROG

(MAGMA) I:=[1, 1, 5, 11, 115, 241, 1079, 1320, 56519, 57839, 287875, 633589, 6623765, 13881119, 62148241, 76029360]; [n le 16 select I[n] else 57598*Self(n-8)-Self(n-16): n in [1..30]]; // Vincenzo Librandi, Dec 27 2013

CROSSREFS

Cf. A041908, A040454.

Sequence in context: A057178 A056265 A302144 * A041048 A222568 A248253

Adjacent sequences:  A041906 A041907 A041908 * A041910 A041911 A041912

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 27 2013

STATUS

approved

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Last modified June 20 05:01 EDT 2019. Contains 324229 sequences. (Running on oeis4.)