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

A009069

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

Terms

    a(0) =1a(1) =-1a(2) =1a(3) =47a(4) =-1343a(5) =8671a(6) =2436545a(7) =-249528945a(8) =10176663169

External references