2017677153

Appears in sequences

• arctan(sec(x)*arctan(x))=x-1/3!*x^3+33/5!*x^5-1377/7!*x^7+99649/9!*x^9...at n=6A012805
• Expansion of e.g.f. log(cosh(x) + arctanh(x)).at n=13A013192