

A176327


Numerators of the rational sequence with e.g.f. (x/2)*(1+exp(x))/(1exp(x)).


9



1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 5, 0, 691, 0, 7, 0, 3617, 0, 43867, 0, 174611, 0, 854513, 0, 236364091, 0, 8553103, 0, 23749461029, 0, 8615841276005, 0, 7709321041217, 0, 2577687858367, 0, 26315271553053477373, 0, 2929993913841559, 0, 261082718496449122051
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OFFSET

0,11


COMMENTS

Numerator of the Bernoulli number B_n, except B(1)=0.
A027641 is the main entry for this sequence, which is only a minor variation.  N. J. A. Sloane, Nov 29 2010.
This could formally be defined by building the arithmetic mean of the numerators in A164555(n) and A027641(n).


LINKS

Table of n, a(n) for n=0..40.


FORMULA

a(2n+1) = 0. a(2n ) = A000367(n).
a(n) = A164555(n) = A027641(n) if n <>1.


MAPLE

seq(numer((bernoulli(i, 0)+bernoulli(i, 1))/2), i=0..40); # Peter Luschny, Jun 17 2012


CROSSREFS

Cf. A176289 (denominators), A027642, A141056, A164020, A165823
Sequence in context: A036946 A027641 A164555 * A226156 A215616 A249737
Adjacent sequences: A176324 A176325 A176326 * A176328 A176329 A176330


KEYWORD

sign


AUTHOR

Paul Curtz, Apr 15 2010


EXTENSIONS

New name from Peter Luschny, Jun 18 2012


STATUS

approved



