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A041844
Numerators of continued fraction convergents to sqrt(444).
2
21, 295, 12411, 174049, 7322469, 102688615, 4320244299, 60586108801, 2548936813941, 35745701503975, 1503868399980891, 21089903301236449, 887279807051911749, 12443007202028000935, 523493582292227951019
OFFSET
0,1
FORMULA
G.f.: -(x^3-21*x^2-295*x-21)/(x^4-590*x^2+1). - Vincenzo Librandi, Nov 10 2013
a(n) = 590*a(n-2)-a(n-4). - Vincenzo Librandi, Nov 10 2013
MATHEMATICA
Numerator[Convergents[Sqrt[444], 20]] (* Harvey P. Dale, Oct 01 2013 *)
CoefficientList[Series[-(x^3 - 21 x^2 - 295 x - 21)/(x^4 - 590 x^2 + 1), {x, 0, 25}], x] (* Vincenzo Librandi, Nov 10 2013 *)
PROG
(Magma) I:=[21, 295, 12411, 174049]; [n le 4 select I[n] else 590*Self(n-2)-Self(n-4): n in [1..20]]; // Vincenzo Librandi, Nov 10 2013
CROSSREFS
Cf. A041845.
Sequence in context: A021864 A020570 A025940 * A295779 A021829 A019943
KEYWORD
nonn,cofr,frac,easy,less
AUTHOR
STATUS
approved