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A041845
Denominators of continued fraction convergents to sqrt(444).
2
1, 14, 589, 8260, 347509, 4873386, 205029721, 2875289480, 120967187881, 1696415919814, 71370435820069, 1000882517400780, 42108436166652829, 590518988850540386, 24843905967889349041, 348405202539301426960, 14657862412618549281361, 205558478979198991366014
OFFSET
0,2
FORMULA
G.f.: -(x^2-14*x-1) / (x^4-590*x^2+1). - Colin Barker, Nov 26 2013
a(n) = 590*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Dec 25 2013
MATHEMATICA
Denominator[Convergents[Sqrt[444], 30]] (* Vincenzo Librandi, Dec 25 2013 *)
LinearRecurrence[{0, 590, 0, -1}, {1, 14, 589, 8260}, 20] (* Harvey P. Dale, Aug 07 2022 *)
PROG
(Magma) I:=[1, 14, 589, 8260]; [n le 4 select I[n] else 590*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Dec 25 2013
CROSSREFS
Sequence in context: A232369 A218412 A129007 * A205327 A291121 A279294
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 26 2013
STATUS
approved