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

A354176

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

Terms

    a(0) =1a(1) =0a(2) =-2a(3) =8a(4) =-24a(5) =-16a(6) =-720a(7) =12032a(8) =0a(9) =-7936a(10) =-3628800a(11) =-58190848a(12) =-479001600a(13) =-22368256a(14) =87178291200

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