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%I #6 Mar 30 2012 18:37:27
%S 1,8,71,478,3248,19674,116885,655064,3602627,19082622,99353815,
%T 503974610,2518347829,12341129010,59691674707,284343349874,
%U 1339171125620,6229010760982,28686750790598,130740792179088,590661906472634,2644740541614160
%N G.f.: exp( Sum_{n>=1} 2*sigma(n*3^n)*x^n/n ).
%e G.f.: A(x) = 1 + 8*x + 71*x^2 + 478*x^3 + 3248*x^4 + 19674*x^5 +...
%e log(A(x)) = 8*x + 78*x^2/2 + 242*x^3/3 + 1694*x^4/4 + 4368*x^5/5 + 19680*x^6/6 + 52480*x^7/7 +...+ 2*sigma(n*3^n)*x^n/n +...
%o (PARI) {a(n)=polcoeff(exp(sum(m=1, n, 2*sigma(m*3^m)*x^m/m)+x*O(x^n)), n)}
%Y Cf. A176310, A193103, A193104.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Jul 15 2011
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