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%I #17 May 14 2021 02:52:55
%S 1,-1,-2,-2,-1,2,6,11,15,16,11,-2,-26,-61,-105,-152,-192,-209,-183,
%T -89,98,400,830,1385,2035,2715,3314,3668,3556,2703,790,-2521,-7550,
%U -14542,-23591,-34546,-46901,-59670,-71261,-79358,-80830,-71690,-47133,-1684,70504,175168,317232
%N Expansion of Product_{k>=1} (1 - x^k/(1 - x)).
%H Seiichi Manyama, <a href="/A307599/b307599.txt">Table of n, a(n) for n = 0..500</a>
%F G.f.: exp( - Sum_{k>=1} x^k * Sum_{d|k} 1/(d*(1-x)^d)).
%t m = 46; CoefficientList[Series[Product[1 - x^k/(1 - x), {k, 1, m}], {x, 0, m}], x] (* _Amiram Eldar_, May 14 2021 *)
%o (PARI) N=66; x='x+O('x^N); Vec(prod(k=1, N, 1-x^k/(1-x)))
%o (PARI) N=66; x='x+O('x^N); Vec(exp(-sum(k=1, N, x^k*sumdiv(k, d, 1/(d*(1-x)^d)))))
%Y Convolution inverse of A227682.
%Y Cf. A126348, A307601, A307602.
%K sign
%O 0,3
%A _Seiichi Manyama_, Apr 17 2019