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%I #15 Jan 10 2022 02:50:01
%S 1,4,13,36,90,208,455,948,1901,3688,6955,12792,23019,40612,70395,
%T 120072,201822,334684,548158,887500,1421602,2254460,3541928,5515900,
%U 8519173,13055208,19859113,29998024,45012751,67116436,99472320,146580028,214811311,313149460
%N Expansion of Product_{k>=1} (1-q^(2*k))/(1-q^k)^4.
%H Seiichi Manyama, <a href="/A350642/b350642.txt">Table of n, a(n) for n = 0..10000</a>
%H George E. Andrews and Peter Paule, <a href="https://doi.org/10.1016/j.jnt.2021.09.008">MacMahon's partition analysis XIII: Schmidt type partitions and modular forms</a>, Journal of Number Theory Available online 22 October 2021. See 4.1 p. 8.
%t m = 50; CoefficientList[Series[Product[(1 - q^(2*k))/(1 - q^k)^4, {k, 1, m}], {q, 0, m}], q] (* _Amiram Eldar_, Jan 09 2022 *)
%o (PARI) lista(nn) = my(q='q+O('q^nn)); Vec(prod(k=1, nn, (1-q^(2*k))/(1-q^k)^4));
%Y Cf. A350643, A350644.
%K nonn
%O 0,2
%A _Michel Marcus_, Jan 09 2022