Product_{n>=1} 1 / (1 - a(n)*x^n/n!) = 1 + tanh(x).

A353912

Product_{n>=1} 1 / (1 - a(n)*x^n/n!) = 1 + tanh(x).

Terms

    a(0) =1a(1) =-2a(2) =-2a(3) =-16a(4) =-24a(5) =64a(6) =-720a(7) =-23808a(8) =-35840a(9) =282368a(10) =-3628800a(11) =-75458560a(12) =-479001600a(13) =5315078144a(14) =-82614884352

External references