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%I #10 Nov 01 2013 16:23:02
%S 1,0,0,3,0,7,90,497,1176,4471,185094,1537877,1964028,-3633797,
%T 1848048202,22918664225,-75962374768,-1620122697905,67890529994062,
%U 1135357942624877,-11941170933349628,-252473078493886301
%N exp(tan(x)-arcsinh(x)) = 1+3/3!*x^3+7/5!*x^5+90/6!*x^6+497/7!*x^7...
%H Alois P. Heinz, <a href="/A013450/b013450.txt">Table of n, a(n) for n = 0..200</a>
%F E.g.f.: exp(tan(x))/(x+sqrt(1+x^2)). - _Vaclav Kotesovec_, Nov 01 2013
%F a(n) ~ -2*cos(Pi*n/2-tanh(1)) * n^(n-1) / exp(n). - _Vaclav Kotesovec_, Nov 01 2013
%t CoefficientList[Series[Exp[Tan[x]-ArcSinh[x]], {x, 0, 20}], x]* Range[0, 20]! (* _Vaclav Kotesovec_, Nov 01 2013 *)
%K sign
%O 0,4
%A Patrick Demichel (patrick.demichel(AT)hp.com)