%I #4 Feb 24 2012 12:50:44
%S 1,1,1,-3,-15,41,561,-1243,-40415,58001,4825121,-1956083,-866056815,
%T -740509639,218527875281,509169335477,-73838559553215,
%U -295854887910879,32207514779999041,189240977761969437
%N exp(arctan(tanh(x)))=1+x+1/2!*x^2-3/3!*x^3-15/4!*x^4+41/5!*x^5...
%K sign
%O 0,4
%A Patrick Demichel (patrick.demichel(AT)hp.com)