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%I #6 Mar 27 2019 03:56:09
%S 1,1,0,-4,-1,47,17,-1111,-12,43476,-49665,-2391805,7528897,168436465,
%T -1052303380,-14234148280,161462347715,1288890088835,-27585406164839,
%U -91839429007223,5125915000647712,-6443738757309888,-1013794188308572677,6728499674632962055,205866724424357904465
%N Expansion of e.g.f. exp(exp(x*exp(-x)) - 1).
%H M. Bernstein and N. J. A. Sloane, <a href="http://arXiv.org/abs/math.CO/0205301">Some canonical sequences of integers</a>, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to arXiv version]
%H M. Bernstein and N. J. A. Sloane, <a href="/A003633/a003633_1.pdf">Some canonical sequences of integers</a>, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to Lin. Alg. Applic. version together with omitted figures]
%H N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F a(n) = Sum_{k=0..n} (-k)^(n-k)*binomial(n,k)*Bell(k), where Bell() = A000110.
%p a:=series(exp(exp(x*exp(-x))-1),x=0,25): seq(n!*coeff(a, x, n), n=0..24); # _Paolo P. Lava_, Mar 26 2019
%t nmax = 24; CoefficientList[Series[Exp[Exp[x Exp[-x]] - 1], {x, 0, nmax}], x] Range[0, nmax]!
%t a[n_] := a[n] = Sum[(-k)^(n - k) Binomial[n, k] BellB[k], {k, n}]; a[0] = 1; Table[a[n], {n, 0, 24}]
%Y Cf. A000110, A003725, A007550.
%K sign
%O 0,4
%A _Ilya Gutkovskiy_, Jun 25 2018