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A041173
Denominators of continued fraction convergents to sqrt(96).
2
1, 1, 4, 5, 94, 99, 391, 490, 9211, 9701, 38314, 48015, 902584, 950599, 3754381, 4704980, 88444021, 93149001, 367891024, 461040025, 8666611474, 9127651499, 36049565971, 45177217470, 849239480431, 894416697901, 3532489574134, 4426906272035, 83216802470764
OFFSET
0,3
FORMULA
G.f.: (1 +x +4*x^2 +5*x^3 -4*x^4 +x^5 -x^6)/(1 -98*x^4 +x^8). - Vincenzo Librandi, Dec 12 2013
a(n) = 98*a(n-4) - a(n-8). - Vincenzo Librandi, Dec 12 2013
MATHEMATICA
Denominator[Convergents[Sqrt[96], 201]] (* or *) CoefficientList[Series[(1 + x + 4 x^2 + 5 x^3 - 4 x^4 + x^5 - x^6)/(1 - 98 x^4 + x^8), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 12 2013 *)
PROG
(Magma) I:=[1, 1, 4, 5, 94, 99, 391, 490]; [n le 8 select I[n] else 98*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Dec 12 2013
CROSSREFS
Cf. A041172.
Sequence in context: A192084 A376048 A078985 * A005512 A331584 A052320
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Vincenzo Librandi, Dec 12 2013
STATUS
approved