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%I #3 Aug 27 2018 06:51:12
%S 1,1,6,15,45,105,302,668,1664,3830,8793,19350,43265,92552,198418,
%T 418128,869999,1787964,3651028,7353349,14697367,29139447,57225893,
%U 111572329,216001937,415000057,792008753,1502559866,2831393559,5305614223,9885825732,18318165218
%N Expansion of Product_{i>=1, j>=1, k>=1} (1 + i*j*k*x^(i*j*k)).
%t nmax = 40; CoefficientList[Series[Product[Product[Product[(1+i*j*k*x^(i*j*k)), {i, 1, nmax}], {j, 1, nmax}], {k, 1, nmax}], {x, 0, nmax}], x]
%Y Cf. A022629, A318416.
%Y Cf. A000009, A280541, A318414, A318481.
%K nonn
%O 0,3
%A _Vaclav Kotesovec_, Aug 27 2018