Expansion of e.g.f.: exp(tanh(arctan(x)))=1+x+1/2!*x^2-3/3!*x^3-15/4!*x^4+41/5!*x^5...

A012256

Expansion of e.g.f.: exp(tanh(arctan(x)))=1+x+1/2!*x^2-3/3!*x^3-15/4!*x^4+41/5!*x^5...

Terms

    a(0) =1a(1) =1a(2) =1a(3) =-3a(4) =-15a(5) =41a(6) =561a(7) =-1019a(8) =-38623a(9) =12305a(10) =4206881a(11) =7478221a(12) =-661302639a(13) =-3005647943a(14) =140958927825

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