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%I #6 Nov 13 2021 17:02:09
%S 2,12,20,56,52,168,156,432,614,1272,2092,4784,8244,17064,33160,67040,
%T 131140,265092,524364,1053616,2098200,4202760,8388700,16797216,
%U 33554902,67141944,134221232,268503312,536871028,1073881488,2147483772
%N a(n) = Sum_{d|n} d*2^(n/d)*tau(d).
%C tau(n) = A000005(n) = the number of divisors of n.
%H Harvey P. Dale, <a href="/A174478/b174478.txt">Table of n, a(n) for n = 1..1000</a>
%F Logarithmic derivative of A174477.
%t Table[With[{d=Divisors[n]},Total[d 2^(n/d) DivisorSigma[0,d]]],{n,40}] (* _Harvey P. Dale_, Nov 13 2021 *)
%o (PARI) {a(n)=sumdiv(n,d,d*2^(n/d)*sigma(d,0))}
%Y Cf. A174477, A000005 (tau).
%K nonn
%O 1,1
%A _Paul D. Hanna_, Apr 04 2010
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