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A041275
Denominators of continued fraction convergents to sqrt(150).
3
1, 4, 97, 392, 9505, 38412, 931393, 3763984, 91267009, 368832020, 8943235489, 36141773976, 876345810913, 3541525017628, 85872946233985, 347033309953568, 8414672385119617, 34005722850432036, 824552020795488481
OFFSET
0,2
FORMULA
G.f.: (1 +4*x -x^2)/(x^4 -98*x^2 +1). - Vincenzo Librandi, Dec 14 2013
a(n) = 98*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 14 2013
MATHEMATICA
Denominator[Convergents[Sqrt[150], 30]] (* or *) CoefficientList[Series[(1 + 4 x - x^2)/(x^4 - 98 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 14 2013 *)
PROG
(Magma) I:=[1, 4, 97, 392]; [n le 4 select I[n] else 98*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 14 2013
CROSSREFS
Cf. A041274.
Sequence in context: A309483 A333539 A356808 * A024384 A368004 A320358
KEYWORD
nonn,frac,easy
AUTHOR
STATUS
approved