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A041270
Numerators of continued fraction convergents to sqrt(148).
2
12, 73, 1764, 10657, 257532, 1555849, 37597908, 227143297, 5489037036, 33161365513, 801361809348, 4841332221601, 116993335127772, 706801342988233, 17080225566845364, 103188154744060417, 2493595939424295372
OFFSET
0,1
FORMULA
G.f.: (12+73*x+12*x^2-x^3)/(1-146*x^2+x^4). - Vincenzo Librandi, Nov 01 2013
a(n) = 146*a(n-2)-a(n-4). - Vincenzo Librandi, Nov 01 2013
MATHEMATICA
Numerator[Convergents[Sqrt[148], 30]] (* or *) CoefficientList[Series[(12 + 73 x + 12 x^2 - x^3)/(1 - 146 x^2 + x^4), {x, 0, 25}], x](* Vincenzo Librandi, Nov 01 2013 *)
LinearRecurrence[{0, 146, 0, -1}, {12, 73, 1764, 10657}, 20] (* Harvey P. Dale, Apr 28 2018 *)
PROG
(Magma) I:=[12, 73, 1764, 10657]; [n le 4 select I[n] else 146*Self(n-2)-Self(n-4): n in [1..25]]; // Vincenzo Librandi, Nov 01 2013
CROSSREFS
Cf. A041271.
Sequence in context: A024014 A069039 A156196 * A055912 A346446 A064121
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved