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%I #6 Jun 26 2024 15:05:42
%S 0,1,1,4,1,10,1,12,6,14,1,36,1,18,16,32,1,51,1,52,20,26,1,104,10,30,
%T 27,68,1,124,1,80,28,38,24,180,1,42,32,152,1,164,1,100,87,50,1,272,14,
%U 115,40,116,1,216,32,200,44,62,1,432,1,66,111,192,36,244,1,148
%N a(n) = n * Sum_{p|n, p prime} tau(n/p) / p.
%F a(p^k) = k*p^(k-1), for prime p and k >= 1. - _Wesley Ivan Hurt_, Jun 26 2024
%t Table[n*DivisorSum[n, DivisorSigma[0, n/#]/# &, PrimeQ[#] &], {n, 80}]
%Y Cf. A000005 (tau), A062799, A319131, A369893.
%K nonn,easy
%O 1,4
%A _Wesley Ivan Hurt_, Feb 04 2024