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%I #22 Aug 04 2024 04:16:20
%S 1,1,-1,-4,9,60,-175,-2154,6433,140984,-404063,-14300174,38333361,
%T 2070386084,-5007071823,-406148697538,844312637249,103808494182512,
%U -173366392362431,-33528470038125974,40208654504239441
%N Expansion of e.g.f. exp(arctan(x)/exp(x)).
%C The inner function is arctan(x)/exp(x) = 2*x/2! - 6*x^2/2! + 4*x^3/3! + 20*x^4/4! + 54*x^5/5! - 770*x^6/6! - 2232*x^7/7! + ...
%H G. C. Greubel, <a href="/A013571/b013571.txt">Table of n, a(n) for n = 0..400</a>
%e exp(arctan(x)/exp(x)) = 1 + x - 1/2!*x^2 - 4/3!*x^3 + 9/4!*x^4 + 60/5!*x^5 + ...
%t Table[n!*SeriesCoefficient[Exp[ArcTan[x]/Exp[x]], {x, 0, n}], {n,0,50}] (* _G. C. Greubel_, Nov 19 2016 *)
%o (PARI) my(x='x + O('x^50)); Vec(serlaplace(exp(atan(x)/exp(x)))) \\ _G. C. Greubel_, Nov 19 2016
%K sign
%O 0,4
%A Patrick Demichel (patrick.demichel(AT)hp.com)