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

A009068

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

Terms

    a(0) =1a(1) =-1a(2) =-15a(3) =-513a(4) =-31007a(5) =-2881089a(6) =-376412847a(7) =-64825974593

External references