Expansion of e.g.f. log(1 + tanh(x)^2), even powers only.

A009403

Expansion of e.g.f. log(1 + tanh(x)^2), even powers only.

Terms

    a(0) =0a(1) =2a(2) =-28a(3) =992a(4) =-69088a(5) =8110592a(6) =-1448424448a(7) =366436769792

External references