sech(cos(x)*sin(x))=1-1/2!*x^2+21/4!*x^4-717/6!*x^6+46025/8!*x^8...

A012479

sech(cos(x)*sin(x))=1-1/2!*x^2+21/4!*x^4-717/6!*x^6+46025/8!*x^8...

Terms

    a(0) =1a(1) =-1a(2) =21a(3) =-717a(4) =46025a(5) =-4817209a(6) =734055069a(7) =-154121194437

External references