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%I #15 Jun 12 2018 10:23:37
%S 0,0,2,4,12,12,40,28,84,87,164,110,456,200,536,700,1150,592,2304,978,
%T 3756,3164,4004,2508,12592,5871,9740,12036,22302,9128,44824
%N a(n) = tau(n) * (NumberOfPartitions(n) - 1).
%H G. C. Greubel, <a href="/A141668/b141668.txt">Table of n, a(n) for n = 0..5000</a>
%F a(n) = A000005(n)*(A000041(n) - 1) = A000005(n)*A000065(n).
%t f[n_] = DivisorSigma[0, n]*PartitionsP[n] - DivisorSigma[0, n]; Table[f[n], {n, 1, 30}]
%o (PARI) a(n) = if (n, numdiv(n)*(numbpart(n)-1), 0); \\ _Michel Marcus_, Jun 11 2018
%Y Cf. A000005, A000041.
%K nonn
%O 0,3
%A _Roger L. Bagula_ and _Gary W. Adamson_, Sep 06 2008
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