Expansion of e.g.f. cos(sinh(x))/cos(x), even terms only.

A009058

Expansion of e.g.f. cos(sinh(x))/cos(x), even terms only.

Terms

    a(0) =1a(1) =0a(2) =-4a(3) =-56a(4) =-1072a(5) =-34368a(6) =-1781440a(7) =-132000896a(8) =-12912385792

External references