arcsinh(tanh(x)*tan(x)) = 2/2!*x^2-8/6!*x^6+82592/10!*x^10...

A012672

arcsinh(tanh(x)*tan(x)) = 2/2!*x^2-8/6!*x^6+82592/10!*x^10...

Terms

    a(0) =2a(1) =-8a(2) =82592a(3) =-608724608

External references