arctan(cos(x)-sech(x))=-4/4!*x^4+60/6!*x^6-1384/8!*x^8+50520/10!*x^10...

A013486

arctan(cos(x)-sech(x))=-4/4!*x^4+60/6!*x^6-1384/8!*x^8+50520/10!*x^10...

Terms

    a(0) =-4a(1) =60a(2) =-1384a(3) =50520a(4) =-1963564a(5) =-2440620a(6) =24774209456

External references