521329705

Appears in sequences

• Expansion of log(1+tan(x)/cosh(x)).at n=13A009381
• arctan(sec(x)*tanh(x))=x-1/3!*x^3+25/5!*x^5-761/7!*x^7+42065/9!*x^9...at n=6A012835
• Expansion of e.g.f. log(cosh(x) + tan(x)).at n=13A013187