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A141590
a(n) = numerator of Bernoulli(2*n)/(2*n + 1)!. Bisection of A120082.
9
1, 1, -1, 1, -1, 1, -691, 1, -3617, 43867, -174611, 77683, -236364091, 657931, -3392780147, 1723168255201, -7709321041217, 151628697551, -26315271553053477373, 154210205991661, -261082718496449122051, 1520097643918070802691, -2530297234481911294093
OFFSET
0,7
COMMENTS
Numerators of the Taylor expansion coefficients of the Debye function D(1,x) at the even powers of x.
LINKS
Kevin Acres and David Broadhurst, Eta quotients and Rademacher sums, arXiv:1810.07478 [math.NT], 2018.
FORMULA
a(n) = A120082(2*n).
EXAMPLE
Note that a(34) = -125235502160125163977598011460214000388469 but A255505(34) = -4633713579924631067171126424027918014373353.
MAPLE
A141590 := proc(n) A120082(2*n) end:
seq(A141590(n), n=0..30) ; # R. J. Mathar, Sep 03 2009
seq(numer(bernoulli(2*n)/(2*n+1)!), n=0..34); # Peter Luschny, Dec 03 2022
MATHEMATICA
Table[Numerator[BernoulliB[2*n]/(2*n+1)!], {n, 0, 35}] (* G. C. Greubel, Sep 16 2024 *)
PROG
(Magma)
A141590:= func< n | Numerator(BernoulliNumber(2*n)/Factorial(2*n+1)) >;
[A141590(n): n in [0..35]]; // G. C. Greubel, Sep 16 2024
(SageMath)
def A141590(n): return numerator(bernoulli(2*n)/factorial(2*n+1))
[A141590(n) for n in range(36)] # G. C. Greubel, Sep 16 2024
CROSSREFS
KEYWORD
sign,frac
AUTHOR
Paul Curtz, Aug 20 2008
EXTENSIONS
Edited and extended by R. J. Mathar, Sep 03 2009
Edited by Peter Luschny, Dec 03 2022
STATUS
approved