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

A354065

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

Terms

    a(0) =1a(1) =-2a(2) =2a(3) =-8a(4) =56a(5) =-496a(6) =3184a(7) =-22784a(8) =273920a(9) =-4539136a(10) =48104704a(11) =-506000384a(12) =10591523840a(13) =-204528633856

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