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%I #9 Jul 20 2018 03:48:10
%S 1,-31,434,-3627,20367,-84537,296825,-1027805,3586700,-11522204,
%T 33703882,-97807604,289043659,-814257997,2164448117,-5763699428,
%U 15479115951,-40058137473,100379076723,-252617470522,633832842041
%N Expansion of Product_{m>=1} (1+m*q^m)^-31.
%H G. C. Greubel, <a href="/A022723/b022723.txt">Table of n, a(n) for n = 0..1000</a>
%t With[{nmax = 50}, CoefficientList[Series[Product[(1 + k*q^k)^-31, {k, 1, nmax}], {q, 0, nmax}], q]] (* _G. C. Greubel_, Jul 20 2018 *)
%o (PARI) m=50; q='q+O('q^m); Vec(prod(n=1,m,(1+n*q^n)^-31)) \\ _G. C. Greubel_, Jul 20 2018
%K sign
%O 0,2
%A _N. J. A. Sloane_