A133005 Denominators of Blandin-Diaz compositional Bernoulli numbers C_2,n.

1, 1, 3, 6, 45, 54, 63, 540, 405, 810, 13365, 20412, 331695, 306180, 65610, 29160, 6506325, 2296350, 4363065, 757795500, 22733865, 90935460, 203719050, 9672226200, 403009425, 4836113100, 22320522, 2232052200, 267009244425, 6313519080, 3425084100900, 112696315578000, 3018651310125

Offset

0,3

Links

Table of n, a(n) for n=0..32.

Hector Blandin and Rafael Diaz, Compositional Bernoulli numbers, arXiv:0708.0809 [math.CO], 2007-2008, p. 14, first table.

Example

0, 1, -23, 56, -68/45, 193/54, -655/63, 19349/540, -57736/405, 520343/810.

Prog

(PARI) my(x='x+O('x^40)); apply(denominator, concat(0, Vec(serlaplace(serreverse(2*(exp(x)-1-x)/x))))) \\ Michel Marcus, Jan 24 2024

Crossrefs

Numerators are A133004.

Cf. A132092-A132099.

Sequence in context: A001886 A153742 A092198 * A009581 A088674 A203434

Adjacent sequences: A133002 A133003 A133004 * A133006 A133007 A133008

Keyword

frac,nonn

Author

Jonathan Vos Post, Aug 09 2007

Extensions

a(6) corrected and more terms from Michel Marcus, Jan 24 2024

Status

approved