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

A009693

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

Terms

    a(0) =1a(1) =2a(2) =8a(3) =48a(4) =-256a(5) =-6656a(6) =930816a(7) =-94216192a(8) =9099706368a(9) =-822565076992

External references