sech(sinh(x)*cos(x))=1-1/2!*x^2+13/4!*x^4-277/6!*x^6+12185/8!*x^8...

A012570

sech(sinh(x)*cos(x))=1-1/2!*x^2+13/4!*x^4-277/6!*x^6+12185/8!*x^8...

Terms

    a(0) =1a(1) =-1a(2) =13a(3) =-277a(4) =12185a(5) =-840489a(6) =84759717a(7) =-11842313277

External references