A255506 Denominator of Bernoulli(2n)/(2n!).

2, 12, 120, 504, 1440, 3168, 3931200, 8640, 41126400, 579156480, 2395008000, 1001548800, 2615348736000, 5748019200, 21670032384000, 7491404919398400, 21341245685760000, 251073478656000, 24574743184592240640000, 76828484468736000, 65834328341259878400000

Offset

0,1

Links

Table of n, a(n) for n=0..20.

MathOverflow, What can be said about a function given its asymptotic expansion?

Example

The sequence Bernoulli(2n)/(2n!) (n >= 0) begins 1/2, 1/12, -1/120, 1/504, -1/1440, 1/3168, -691/3931200, 1/8640, -3617/41126400, ...

Mathematica

Table[Denominator[BernoulliB[2 n]/(2 n!)], {n, 0, 25}]

Prog

(Magma) [Denominator(Bernoulli(2*n)/(2*Factorial(n))): n in [0..25]]; // Vincenzo Librandi, Feb 24 2015
(PARI) a(n) = denominator(bernfrac(2*n)/(2*n!)); \\ Michel Marcus, Feb 24 2015
(Sage) [denominator(bernoulli(2*n)/(2*factorial(n))) for n in (0..25)] # Bruno Berselli, Feb 24 2015

Crossrefs

Cf. A255505 (numerator).

Sequence in context: A328857 A373532 A295864 * A095717 A089431 A119701

Adjacent sequences: A255503 A255504 A255505 * A255507 A255508 A255509

Keyword

nonn,frac

Author

Jean-François Alcover, Feb 24 2015

Status

approved