Expansion of tanh(tan(sin(x))).

A009807

Expansion of tanh(tan(sin(x))).

Terms

    a(0) =1a(1) =-1a(2) =-7a(3) =167a(4) =1553a(5) =-238481a(6) =4553a(7) =1254638551a(8) =-35872740703

External references