cosh(arcsin(arcsinh(x)))=1+1/2!*x^2+1/4!*x^4+49/6!*x^6+1/8!*x^8...

A012120

cosh(arcsin(arcsinh(x)))=1+1/2!*x^2+1/4!*x^4+49/6!*x^6+1/8!*x^8...

Terms

    a(0) =1a(1) =1a(2) =1a(3) =49a(4) =1a(5) =83361a(6) =-2206335a(7) =961321425a(8) =-96313079295

External references