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A041547
Denominators of continued fraction convergents to sqrt(291).
2
1, 17, 579, 9860, 335819, 5718783, 194774441, 3316884280, 112968839961, 1923787163617, 65521732402939, 1115793238013580, 38002491824864659, 647158154260712783, 22041379736689099281, 375350613677975400560, 12783962244787852718321
OFFSET
0,2
FORMULA
G.f.: -(x^2-17*x-1) / (x^4-580*x^2+1). - Colin Barker, Nov 18 2013
a(n) = 580*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Dec 20 2013
MATHEMATICA
Denominator[Convergents[Sqrt[291], 40]] (* Harvey P. Dale, Apr 20 2012 *)
CoefficientList[Series[(1 + 17 x - x^2)/(x^4 - 580 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 20 2013 *)
PROG
(Magma) I:=[1, 17, 579, 9860]; [n le 4 select I[n] else 580*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 20 2013
CROSSREFS
Sequence in context: A191865 A249862 A056771 * A041544 A202407 A009709
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 18 2013
STATUS
approved