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%I #18 May 16 2018 09:55:13
%S 1,0,1,10,47,201,849,3578,15147,64516,276268,1188342,5130987,22226036,
%T 96543989,420368843,1834203939,8018057328,35107961157,153950675566,
%U 675978772306,2971700764920,13078268135661,57613905606250,254038914924767,1121081799217206,4951199308679965
%N a(n) = [x^n] Product_{k>=1} ((1 + x^k)/(1 + x^(n*k)))^n.
%C Number of partitions of n into 2 or more distinct parts, with n types of each part. - _Ilya Gutkovskiy_, May 16 2018
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F a(n) ~ c * d^n / sqrt(n), where d = A270914 = 4.502476747617354487738... and c = 0.2605422331424384694... - _Vaclav Kotesovec_, May 16 2018
%t Table[SeriesCoefficient[Product[((1 + x^k)/(1 + x^(n k)))^n, {k, 1, n}], {x, 0, n}], {n, 0, 26}]
%t Table[SeriesCoefficient[Product[(1 + x^k)^n, {k, 1, n - 1}], {x, 0, n}], {n, 0, 26}]
%t Table[SeriesCoefficient[(QPochhammer[-1, x, 1 + n]/QPochhammer[-1, x^n, 1 + n])^n, {x, 0, n}], {n, 0, 26}]
%Y Cf. A058576, A073252, A111133, A255526, A270913, A304625.
%K nonn
%O 0,4
%A _Ilya Gutkovskiy_, May 15 2018
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