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A041897
Denominators of continued fraction convergents to sqrt(470).
2
1, 1, 3, 25, 53, 78, 3329, 3407, 10143, 84551, 179245, 263796, 11258677, 11522473, 34303623, 285951457, 606206537, 892157994, 38076842285, 38969000279, 116014842843, 967087743023, 2050190328889, 3017278071912, 128775869349193, 131793147421105
OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 3382, 0, 0, 0, 0, 0, -1).
FORMULA
G.f.: -(x^10 -x^9 +3*x^8 -25*x^7 +53*x^6 -78*x^5 -53*x^4 -25*x^3 -3*x^2 -x -1) / (x^12 -3382*x^6 +1). - Colin Barker, Nov 27 2013
a(n) = 3382*a(n-6) - a(n-12) for n>11. - Vincenzo Librandi, Dec 26 2013
MATHEMATICA
Denominator[Convergents[Sqrt[470], 30]] (* Vincenzo Librandi, Dec 26 2013 *)
PROG
(Magma) I:=[1, 1, 3, 25, 53, 78, 3329, 3407, 10143, 84551, 179245, 263796]; [n le 12 select I[n] else 3382*Self(n-6)-Self(n-12): n in [1..50]]; // Vincenzo Librandi, Dec 26 2013
CROSSREFS
Sequence in context: A145609 A259923 A120285 * A356594 A242974 A006222
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 27 2013
STATUS
approved