cosh(arctanh(x)*arctan(x)) = 1+12/4!*x^4+13328/8!*x^8+123701952/12!*x^12...

A012735

cosh(arctanh(x)*arctan(x)) = 1+12/4!*x^4+13328/8!*x^8+123701952/12!*x^12...

Terms

    a(0) =1a(1) =12a(2) =13328a(3) =123701952

External references