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

A009521

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

Terms

    a(0) =1a(1) =-1a(2) =-7a(3) =55a(4) =2897a(5) =-5105a(6) =-7252983a(7) =-341550201a(8) =43255573537

External references