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Expansion of e.g.f. ( Product_{k>0} (1+x^k)^(1/k!) )^x.
1

%I #13 Aug 13 2022 11:29:48

%S 1,0,2,0,24,-55,630,-2723,30968,-294327,3047320,-30255379,387690732,

%T -5565964391,77090414492,-1114263777885,18473122449616,

%U -331776991760303,6106973926830192,-112710455017397639,2233663985151902860,-50049383051597936559

%N Expansion of e.g.f. ( Product_{k>0} (1+x^k)^(1/k!) )^x.

%F a(0) = 1, a(1) = 0; a(n) = Sum_{k=2..n} k * A352013(k-1) * binomial(n-1,k-1) * a(n-k).

%o (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(prod(k=1, N, (1+x^k)^(1/k!))^x))

%o (PARI) a352013(n) = (n-1)!*sumdiv(n, d, (-1)^(n/d+1)/(d-1)!);

%o a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=2, i, j*a352013(j-1)*binomial(i-1, j-1)*v[i-j+1])); v;

%Y Cf. A352013, A356402, A356575.

%K sign

%O 0,3

%A _Seiichi Manyama_, Aug 12 2022