Expansion of log(1+tanh(x)*x).A009399Expansion of log(1+tanh(x)*x).Terms a(0) =0a(1) =2a(2) =-20a(3) =576a(4) =-33312a(5) =3258880a(6) =-485139456a(7) =102300807168External referencesoeis: A009399