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%I #15 Sep 23 2019 12:35:31
%S 1,1,1,1,2,3,3,3,4,6,8,9,9,11,15,20,21,20,24,36,48,46,41,52,80,100,88,
%T 74,103,170,207,166,124,198,354,409,269,162,369,745,802,382,136,706,
%U 1585,1515,328,-178,1422,3481,2822,-387,-1283,3144,7816,4951,-3451,-4472,7694,18055
%N Expansion of Product_{k>=1} (1 + x^k/(1 + x^(2*k)/(1 + x^(3*k)))).
%H Seiichi Manyama, <a href="/A327718/b327718.txt">Table of n, a(n) for n = 0..1000</a>
%t nmax = 60; CoefficientList[Series[Product[(1 - x^(5*k)) / ((1 - x^k)*(1 + x^(2*k) + x^(3*k))), {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Sep 23 2019 *)
%o (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, 1+x^k/(1+x^(2*k)/(1+x^(3*k)))))
%Y Convolution inverse of A327686.
%Y Cf. A327716, A327717, A327719, A327720.
%K sign,look
%O 0,5
%A _Seiichi Manyama_, Sep 23 2019