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E.g.f.: 1/Product_{k>=1} (1-x^k)^(x^k).
1

%I #8 Mar 13 2015 12:15:31

%S 1,0,2,3,44,90,2394,6720,202544,1041768,27369000,170418600,5835999432,

%T 41711464080,1489935696144,14980499777880,519279726915840,

%U 5837621201012160,232228922844775104,2946339663605953920,122979308145781345920,1869847203939341074560

%N E.g.f.: 1/Product_{k>=1} (1-x^k)^(x^k).

%H Vaclav Kotesovec, <a href="/A255969/b255969.txt">Table of n, a(n) for n = 0..440</a>

%H Vaclav Kotesovec, <a href="/A034691/a034691_1.pdf">Asymptotics of sequence A034691</a>

%F log(a(n)) ~ 2*sqrt(n).

%t nmax=20; CoefficientList[Series[Product[1/(1-x^k)^(x^k),{k,1,nmax}],{x,0,nmax}],x] * Range[0, nmax]!

%t nmax=20; CoefficientList[Series[Exp[Sum[1/(k*(1/x^(k+1)-1)),{k,1,nmax}]],{x,0,nmax}],x] * Range[0,nmax]!

%Y Cf. A034691, A034899.

%K nonn

%O 0,3

%A _Vaclav Kotesovec_, Mar 12 2015