Expansion of e.g.f. cos(x/cosh(x)) (even powers only).

A009119

Expansion of e.g.f. cos(x/cosh(x)) (even powers only).

Terms

    a(0) =1a(1) =-1a(2) =13a(3) =-301a(4) =11705a(5) =-698521a(6) =59340997a(7) =-6782462597

External references