This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A159604 #6 Nov 26 2022 21:15:18
%S A159604 1,1,6,43,856,10744,608375,14284223,551011548,19119025101,
%T A159604 874788949035,37896009869060,20683158266928833,1799893777863733707,
%U A159604 93147805938921355288,3757831283217050847983,180287028377782585130749
%N A159604 G.f.: A(x) = exp( Sum_{n>=1} [ Sum_{k>=1} sigma(n,k)*x^k ]^n/n ).
%C A159604 Define sigma(n,k) = Sum_{d|n} d^k.
%H A159604 Paul D. Hanna, <a href="/A159604/b159604.txt">Table of n, a(n) for n = 0..510</a>
%e A159604 G.f.: A(x) = 1 + x + 6*x^2 + 43*x^3 + 856*x^4 + 10744*x^5 +...
%e A159604 log(A(x)) = Sum_{n>=1} [sigma(n)*x + sigma(n,2)*x^2 + sigma(n,3)*x^3 +...]^n/n.
%o A159604 (PARI) {a(n)=local(A=1+x);for(i=1,n,A=exp(sum(m=1,n,sum(k=1,n,sigma(m,k)*x^k+x*O(x^n))^m/m)));polcoeff(A,n)}
%o A159604 for(n=0,20,print1(a(n),", "))
%Y A159604 Cf. variants: A159595, A156217.
%K A159604 nonn
%O A159604 0,3
%A A159604 _Paul D. Hanna_, May 16 2009