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%I #41 Jan 24 2022 04:40:29
%S 1,-1,-2,-2,-2,1,4,13,22,36,47,54,37,-11,-129,-346,-709,-1257,-2023,
%T -2979,-4014,-4836,-4851,-3041,2310,13785,35186,71598,129624,216732,
%U 340488,505769,710775,938823,1146714,1244936,1070745,347604,-1366923,-4751316
%N Expansion of Product_{k>=1} (1-x^k/Product_{j=1..k} (1-x^j)).
%t a[n_] := SeriesCoefficient[Product[1 - x^k/Product[1 - x^j, {j, 1, k}], {k, 1, n}], {x, 0, n}]; Table[a[n], {n, 0, 39}] (* _Robert P. P. McKone_, Jan 18 2022 *)
%o (PARI) my(N=40, x='x+O('x^N)); Vec(prod(k=1, N, 1-x^k/prod(j=1, k, 1-x^j)))
%Y Convolution inverse of A141199.
%K sign
%O 0,3
%A _Seiichi Manyama_, Jan 18 2022