cosh(arctan(arcsinh(x)))=1+1/2!*x^2-11/4!*x^4+349/6!*x^6-22007/8!*x^8...

A012220

cosh(arctan(arcsinh(x)))=1+1/2!*x^2-11/4!*x^4+349/6!*x^6-22007/8!*x^8...

Terms

    a(0) =1a(1) =1a(2) =-11a(3) =349a(4) =-22007a(5) =2312601a(6) =-365164227a(7) =80916522933

External references