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%I #2 Mar 30 2012 18:37:21
%S 1,1,5,32,4138,7371,362821209,363768114,4399869984980,4692111613957,
%T 100023774005024513,100145112875103405,137370551968043406735177291498,
%U 137370551970759432867153686743,687082347540023318264721577813
%N G.f.: exp( Sum_{n>=1} A174472(n)*x^n/n ) where A174472(n) = Sum_{d|n} d^sigma(d).
%o (PARI) {a(n)=polcoeff(exp(sum(m=1,n,x^m/m*sumdiv(m,d,d^sigma(d)))+x*O(x^n)),n)}
%Y Cf. A174472, A000203 (sigma).
%K nonn
%O 0,3
%A _Paul D. Hanna_, Apr 04 2010