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A041639 Denominators of continued fraction convergents to sqrt(338). 2
1, 2, 3, 5, 13, 473, 959, 1432, 2391, 6214, 226095, 458404, 684499, 1142903, 2970305, 108073883, 219118071, 327191954, 546310025, 1419812004, 51659542169, 104738896342, 156398438511, 261137334853, 678673108217, 24693369230665, 50065411569547 (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, 0, 0, 0, 478, 0, 0, 0, 0, 1).

FORMULA

G.f.: -(x^8-2*x^7+3*x^6-5*x^5+13*x^4+5*x^3+3*x^2+2*x+1) / (x^10+478*x^5-1). - Colin Barker, Nov 20 2013

a(n) = 478*a(n-5) + a(n-10) for n>9. - Vincenzo Librandi, Dec 22 2013

MATHEMATICA

Denominator[Convergents[Sqrt[338], 30]] (* Vincenzo Librandi, Dec 22 2013 *)

PROG

(Magma) I:=[1, 2, 3, 5, 13, 473, 959, 1432, 2391, 6214]; [n le 10 select I[n] else 478*Self(n-5)+Self(n-10): n in [1..40]]; // Vincenzo Librandi, Dec 22 2013

CROSSREFS

Cf. A041638, A040319.

Sequence in context: A120494 A038601 A114747 * A006985 A042907 A115347

Adjacent sequences:  A041636 A041637 A041638 * A041640 A041641 A041642

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 20 2013

STATUS

approved

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Last modified September 25 07:19 EDT 2022. Contains 356959 sequences. (Running on oeis4.)