%I #12 Sep 08 2022 08:44:46
%S 1,9,63,354,1764,7947,33294,131049,490437,1756243,6055749,20190402,
%T 65342031,205853535,632948256,1903369146,5608257129,16216492509,
%U 46080035361,128829484620,354757096107,963099596421
%N Expansion of Product_{m>=1} 1/(1 - m*q^m)^9.
%H G. C. Greubel, <a href="/A022733/b022733.txt">Table of n, a(n) for n = 0..1000</a>
%F G.f.: exp(9*Sum_{j>=1} Sum_{k>=1} k^j*x^(j*k)/j). - _Ilya Gutkovskiy_, Feb 07 2018
%t With[{nmax = 50}, CoefficientList[Series[Product[(1 - k*q^k)^-9, {k, 1, nmax}], {q, 0, nmax}], q]] (* _G. C. Greubel_, Jul 25 2018 *)
%o (PARI) m=50; q='q+O('q^m); Vec(prod(n=1,m,(1-n*q^n)^-9)) \\ _G. C. Greubel_, Jul 25 2018
%o (Magma) n:=50; R<x>:=PowerSeriesRing(Integers(), n); Coefficients(R!(&*[(1/(1-m*x^m))^9:m in [1..n]])); // _G. C. Greubel_, Jul 25 2018
%Y Column k=9 of A297328.
%K nonn
%O 0,2
%A _N. J. A. Sloane_
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