G.f.: x * Product_{k>=1} 1/(1 - k^k*x^k)^(a(k)/k).

A308228

G.f.: x * Product_{k>=1} 1/(1 - k^k*x^k)^(a(k)/k).

Terms

    a(0) =1a(1) =1a(2) =3a(3) =30a(4) =1956a(5) =1224510a(6) =9523018859

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