arctan(arctanh(x)+tan(x))=2*x-12/3!*x^3+488/5!*x^5-48608/7!*x^7...

A013173

arctan(arctanh(x)+tan(x))=2*x-12/3!*x^3+488/5!*x^5-48608/7!*x^7...

Terms

    a(0) =2a(1) =-12a(2) =488a(3) =-48608a(4) =9080960a(5) =-2722798848

External references