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A041850
Numerators of continued fraction convergents to sqrt(447).
2
21, 148, 6237, 43807, 1846131, 12966724, 546448539, 3838106497, 161746921413, 1136066556388, 47876542289709, 336271862584351, 14171294770832451, 99535335258411508, 4194655375624115787
OFFSET
0,1
FORMULA
G.f.: -(x^3 - 21*x^2 - 148*x - 21)/(x^4 - 296*x^2 + 1). - Vincenzo Librandi, Nov 10 2013
a(n) = 296*a(n-2) - a(n-4). - Vincenzo Librandi, Nov 10 2013
MATHEMATICA
Numerator[Convergents[Sqrt[447], 30]] (* Harvey P. Dale, Oct 08 2012 *)
CoefficientList[Series[-(x^3 - 21 x^2 - 148 x - 21)/(x^4 - 296 x^2 + 1), {x, 0, 25}], x] (* Vincenzo Librandi, Nov 10 2013 *)
PROG
(Magma) I:=[21, 148, 6237, 43807]; [n le 4 select I[n] else 296*Self(n-2)-Self(n-4): n in [1..20]]; // Vincenzo Librandi, Nov 10 2013
CROSSREFS
Cf. A041851.
Sequence in context: A198183 A259493 A253459 * A239123 A241697 A358994
KEYWORD
nonn,cofr,frac,easy,less
STATUS
approved