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A222412 Denominators in Taylor series expansion of (x/(exp(x) - 1))^(3/2)*exp(x/2). 3

%I

%S 1,4,32,384,10240,40960,61931520,49545216,7927234560,475634073600,

%T 1993133260800,177167400960,48753634065776640,195014536263106560,

%U 39002907252621312000,842462796656620339200,2204424056667635712000,79359266040034885632000

%N Denominators in Taylor series expansion of (x/(exp(x) - 1))^(3/2)*exp(x/2).

%H Alois P. Heinz, <a href="/A222412/b222412.txt">Table of n, a(n) for n = 0..300</a>

%H F. J. Dyson, N. E. Frankel and M. L. Glasser, <a href="http://arxiv.org/abs/1009.4274">Lehmer's Interesting Series</a>, arXiv:1009.4274 [math-ph], 2010-2011.

%H F. J. Dyson, N. E. Frankel and M. L. Glasser, <a href="http://www.jstor.org/stable/10.4169/amer.math.monthly.120.02.116">Lehmer's interesting series</a>, Amer. Math. Monthly, 120 (2013), 116-130.

%H D. H. Lehmer, <a href="https://www.jstor.org/stable/2322496">Interesting series involving the central binomial coefficient</a>, Amer. Math. Monthly, 92(7) (1985), 449-457.

%e The first few fractions are 1, -1/4, -1/32, 5/384, 7/10240, -19/40960, -869/61931520, 715/49545216, ... = A222411/A222412. - _Petros Hadjicostas_, May 14 2020

%p gf:= (x/(exp(x)-1))^(3/2)*exp(x/2):

%p a:= n-> denom(coeff(series(gf, x, n+3), x, n)):

%p seq(a(n), n=0..25); # _Alois P. Heinz_, Mar 02 2013

%t Series[(x/(Exp[x]-1))^(3/2)*Exp[x/2], {x, 0, 25}] // CoefficientList[#, x]& // Denominator (* _Jean-Fran├žois Alcover_, Mar 18 2014 *)

%Y Cf. A222411.

%K nonn,frac

%O 0,2

%A _N. J. A. Sloane_, Feb 28 2013

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Last modified August 4 06:13 EDT 2020. Contains 336201 sequences. (Running on oeis4.)