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%I #16 Feb 26 2022 10:47:57
%S 0,2,3,4,5,5,7,4,3,7,11,7,13,9,8,6,17,8,19,9,10,13,23,9,5,15,6,11,29,
%T 10,31,6,14,19,12,10,37,21,16,9,41,12,43,15,8,25,47,11,7,12,20,17,53,
%U 11,16,11,22,31,59,12,61,33,10,6,18,16,67,21,26,14,71,12,73,39,8,23,18
%N a(n) = Sum_{d|n, p|n, (p^d)|n, p prime} p.
%e a(12) = 7; we have 2^1, 2^2 and 3^1 dividing 12, so a(12) = 2 + 2 + 3 = 7.
%o (PARI) a(n) = my(f=factor(n), d=divisors(f)); sum(k=1, #f~, sum(m=1, #d, if ((n % f[k,1]^d[m]) == 0, f[k,1]))); \\ _Michel Marcus_, Feb 26 2022
%Y Cf. A000005, A027748.
%K nonn
%O 1,2
%A _Wesley Ivan Hurt_, Feb 25 2022
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