%I #23 Sep 08 2022 08:44:46
%S 1,2,5,14,28,64,133,266,513,1000,1873,3420,6257,11078,19585,34192,
%T 58714,99870,168858,281666,467082,768994,1253038,2030658,3269551,
%U 5227868,8304467,13133256,20630535,32250274,50181624,77653530,119634925,183532470,280245365
%N Expansion of Product_{m>=1} (1 + m*q^m)^2.
%H Alois P. Heinz, <a href="/A022630/b022630.txt">Table of n, a(n) for n = 0..10000</a>
%F Self-convolution of A022629. - _Alois P. Heinz_, Dec 28 2017
%F G.f.: exp(2*Sum_{j>=1} Sum_{k>=1} (-1)^(j+1)*k^j*x^(j*k)/j). - _Ilya Gutkovskiy_, Feb 08 2018
%t nn=34; CoefficientList [Series[ Product[(1 + m*q^m)^2, {m, nn}], {q, 0, nn}],q] (* _Robert G. Wilson v_, Feb 08 2018 *)
%o (PARI) m=50; q='q+O('q^m); Vec(prod(n=1,m,(1+n*q^n)^2)) \\ _G. C. Greubel_, Feb 16 2018
%o (Magma) Coefficients(&*[(1+m*x^m)^2:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // _G. C. Greubel_, Feb 16 2018
%Y Column k=2 of A297321.
%Y Cf. A022629, A022694.
%K nonn
%O 0,2
%A _N. J. A. Sloane_