sec(tan(arcsinh(x)))=1+1/2!*x^2+9/4!*x^4+201/6!*x^6+7921/8!*x^8...
A012168
sec(tan(arcsinh(x)))=1+1/2!*x^2+9/4!*x^4+201/6!*x^6+7921/8!*x^8...
Terms
- a(0) =1a(1) =1a(2) =9a(3) =201a(4) =7921a(5) =524081a(6) =48396345a(7) =6493605561
External references
- oeis: A012168