sec(sin(arcsinh(x)))=1+1/2!*x^2-3/4!*x^4+21/6!*x^6-647/8!*x^8...

A012044

sec(sin(arcsinh(x)))=1+1/2!*x^2-3/4!*x^4+21/6!*x^6-647/8!*x^8...

Terms

    a(0) =1a(1) =1a(2) =-3a(3) =21a(4) =-647a(5) =45161a(6) =-4655115a(7) =671831421a(8) =-131445679375

External references