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

A354066

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

Terms

    a(0) =1a(1) =-2a(2) =-2a(3) =8a(4) =-24a(5) =224a(6) =-720a(7) =-1408a(8) =0a(9) =717824a(10) =-3628800a(11) =-47546368a(12) =-479001600a(13) =12431673344a(14) =87178291200a(15) =-68669145088

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