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A042673
Denominators of continued fraction convergents to sqrt(866).
2
1, 2, 5, 7, 201, 208, 617, 1442, 84253, 169948, 424149, 594097, 17058865, 17652962, 52364789, 122382540, 7150552109, 14423486758, 35997525625, 50421012383, 1447785872349, 1498206884732, 4444199641813, 10386606168358, 606867357406577, 1224121320981512
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 84870, 0, 0, 0, 0, 0, 0, 0, -1).
FORMULA
G.f.: -(x^14 -2*x^13 +5*x^12 -7*x^11 +201*x^10 -208*x^9 +617*x^8 -1442*x^7 -617*x^6 -208*x^5 -201*x^4 -7*x^3 -5*x^2 -2*x -1) / (x^16 -84870*x^8 +1). - Colin Barker, Dec 20 2013
a(n) = 84870*a(n-8) - a(n-16) for n>15. - Vincenzo Librandi, Dec 20 2013
MATHEMATICA
Denominator[Convergents[Sqrt[866], 30]] (* Vincenzo Librandi, Dec 20 2013 *)
PROG
(Magma) I:=[1, 2, 5, 7, 201, 208, 617, 1442, 84253, 169948, 424149, 594097, 17058865, 17652962, 52364789, 122382540]; [n le 16 select I[n] else 84870*Self(n-8)-Self(n-16): n in [1..40]]; // Vincenzo Librandi, Dec 20 2013
CROSSREFS
Sequence in context: A242169 A058854 A006275 * A214705 A252283 A007571
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 20 2013
STATUS
approved