sech(tanh(x)+arctan(x))=1-4/2!*x^2+112/4!*x^4-7744/6!*x^6...

A013151

sech(tanh(x)+arctan(x))=1-4/2!*x^2+112/4!*x^4-7744/6!*x^6...

Terms

    a(0) =1a(1) =-4a(2) =112a(3) =-7744a(4) =995840a(5) =-205558144a(6) =62203595776

External references