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A041180
Numerators of continued fraction convergents to sqrt(101).
3
10, 201, 4030, 80801, 1620050, 32481801, 651256070, 13057603201, 261803320090, 5249124005001, 105244283420110, 2110134792407201, 42307940131564130, 848268937423689801, 17007686688605360150, 341002002709530892801
OFFSET
0,1
FORMULA
From Philippe Deléham, Nov 21 2008: (Start)
a(n) = 20*a(n-1) + a(n-2) for n > 1, a(0)=10, a(1)=201.
G.f.: (10+x)/(1-20*x-x^2). (End)
MATHEMATICA
CoefficientList[Series[(10 + x)/(1 - 20 x - x^2), {x, 0, 30}], x] (* Vincenzo Librandi, Oct 30 2013 *)
Numerator[Convergents[Sqrt[101], 20]] (* Bruno Berselli, Oct 30 2013 *)
CROSSREFS
Cf. A041181.
Sequence in context: A279833 A041183 A210168 * A367200 A365177 A027014
KEYWORD
nonn,cofr,frac,easy
STATUS
approved