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A132093 Denominators of Blandin-Diaz compositional Bernoulli numbers (B^sin)_3,n. 3
1, 10, 350, 1050, 57750, 250250, 2388750, 2231250, 1088106250, 137156250, 105761906250, 2289218750, 8842968750, 51289218750, 45049030468750, 3563716406250, 1099667378906250, 4714260332031250, 14142780996093750 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numerators are A132092. Numerators and denominators given only for even n (odd n have numerators = 0).

REFERENCES

J. Riordan, Combinatorial Identities, Wiley, 1968, p. 199. See Table 3.3.

LINKS

Table of n, a(n) for n=1..19.

Hector Blandin and Rafael Diaz, Compositional Bernoulli numbers, p. 8, arXiv:0708.0809 [math.CO], 2007-2008.

FORMULA

(((x^3)/3!)/(sin(x)-x) = SUM[n=0..infinity] (B^sin)_3,n ((x^n)/n!).

EXAMPLE

-1, 0, -1/10, 0, -11/350, 0, -17,1050, 0, -563/57750, 0, -381/250250, 0.

MATHEMATICA

m = 20;

((x^3)/3!)/(Sin[x]-x) + O[x]^(2m) // CoefficientList[#, x]& // #*Range[0, 2m-2]!& // #[[;; ;; 2]]& // Denominator (* Jean-Fran├žois Alcover, Mar 23 2020 *)

CROSSREFS

Cf. A132092-A132106.

Sequence in context: A171583 A060704 A220185 * A217507 A217508 A217509

Adjacent sequences:  A132090 A132091 A132092 * A132094 A132095 A132096

KEYWORD

frac,nonn

AUTHOR

Jonathan Vos Post, Aug 09 2007

EXTENSIONS

More terms from R. J. Mathar, May 25 2008

STATUS

approved

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Last modified September 27 16:20 EDT 2020. Contains 337383 sequences. (Running on oeis4.)