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%I #5 Mar 08 2018 21:17:54
%S 1,2,4,4,10,4,28,4,36,14,44,4,284,4,60,64,202,4,616,4,732,88,92,4,
%T 5740,22,108,112,1404,4,10672,4,1828,136,140,144,42622,4,156,160,
%U 22940,4,28024,4,3420,3172,188,4,266524,30,4344,208,4764,4,58600,224,60204,232,236,4,3464272,4,252,6052,27338,264
%N a(n) = [x^n] Product_{d|n} (1 + x^d)/(1 - x^d).
%H <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F a(n) = 4 if n is a prime (A000040).
%t Table[SeriesCoefficient[Product[(1 + Boole[Mod[n, k] == 0] x^k)/(1 - Boole[Mod[n, k] == 0] x^k), {k, 1, n}], {x, 0, n}], {n, 0, 65}]
%Y Cf. A000040, A015128, A018818, A033630, A300547, A300548.
%K nonn
%O 0,2
%A _Ilya Gutkovskiy_, Mar 08 2018
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