sech(tan(sinh(x)))=1-1/2!*x^2-7/4!*x^4-73/6!*x^6-239/8!*x^8...

A012158

sech(tan(sinh(x)))=1-1/2!*x^2-7/4!*x^4-73/6!*x^6-239/8!*x^8...

Terms

    a(0) =1a(1) =-1a(2) =-7a(3) =-73a(4) =-239a(5) =95311a(6) =12793417a(7) =1502683335a(8) =172513245857

External references