arctanh(sec(x)*sinh(x))=x+6/3!*x^3+140/5!*x^5+8456/7!*x^7...

A012818

arctanh(sec(x)*sinh(x))=x+6/3!*x^3+140/5!*x^5+8456/7!*x^7...

Terms

    a(0) =1a(1) =6a(2) =140a(3) =8456a(4) =957840a(5) =174293856a(6) =46514037440

External references