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%I #8 Sep 16 2021 23:53:03
%S 1,1,6,36,282,2575,28075,340809,4657996,69874305,1145441713,
%T 20279904337,386803154474,7874727448757,170678885319787,
%U 3919163707551187,95029714996046680,2424604353738271201,64940619086990938317,1820746123923294245293,53328181409328560026038
%N E.g.f.: Product_{k>=1} 1 / (1 - x^k)^exp(x).
%C Exponential transform of A002745.
%F E.g.f.: exp( exp(x) * Sum_{k>=1} sigma(k) * x^k / k ).
%F a(0) = 1; a(n) = Sum_{k=1..n} binomial(n-1,k-1) * A002745(k) * a(n-k).
%t nmax = 20; CoefficientList[Series[Product[1/(1 - x^k)^Exp[x], {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!
%t nmax = 20; CoefficientList[Series[Exp[Exp[x] Sum[DivisorSigma[1, k] x^k/k, {k, 1, nmax}]], {x, 0, nmax}], x] Range[0, nmax]!
%t A002745[n_] := Sum[Binomial[n, k] DivisorSigma[1, k] (k - 1)!, {k, 1, n}]; a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k - 1] A002745[k] a[n - k], {k, 1, n}]; Table[a[n], {n, 0, 20}]
%Y Cf. A000203, A002745, A053529, A346545, A346546, A346548.
%K nonn
%O 0,3
%A _Ilya Gutkovskiy_, Sep 16 2021