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%I #4 Mar 15 2021 14:00:11
%S 1,2,4,9,14,29,44,77,120,195,291,453,673,998,1460,2101,3034,4287,6051,
%T 8430,11766,16098,22209,30078,40881,54914,73814,98159,130804,172507,
%U 227608,298254,390262,507721,659731,852727,1100301,1414461,1813262,2317895
%N G.f.: Product_{k>=1} Sum_{n>=0} x^(k*n) / (1 - x^(n+k)).
%e G.f.: A(x) = 1 + 2*x + 4*x^2 + 9*x^3 + 14*x^4 + 29*x^5 + 44*x^6 + 77*x^7 + 120*x^8 + 195*x^9 + 291*x^10 + 453*x^11 + 673*x^12 + 998*x^13 + 1460*x^14 + 2101*x^15 + ...
%o (PARI) {a(n) = my(A = prod(k=1,n, sum(m=0,n, x^(k*m)/(1 - x^(m+k) +x*O(x^n)) )) ); polcoeff(A,n)}
%o for(n=0,40,print1(a(n),", "))
%K nonn
%O 0,2
%A _Paul D. Hanna_, Mar 15 2021