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%I #16 May 25 2021 08:06:59
%S 1,3,4,10,6,47,8,28,21,117,12,118,14,219,248,72,18,177,20,274,472,519,
%T 24,284,55,717,90,494,30,992,32,176,1136,1209,1272,462,38,1503,1576,
%U 628,42,1806,44,1126,834,2187,48,664,105,685,2672,1538,54,639,3096,1100,3328,3453
%N a(n) = n * Sum_{d|n} d^mu(d).
%C If p is prime, a(p) = p * Sum_{d|p} d^mu(d) = p * (1^1 + p^(-1)) = p * (1 + 1/p) = p + 1.
%e a(6) = 6 * Sum_{d|6} d^mu(d) = 6 * (1^1 + 2^(-1) + 3^(-1) + 6^1) = 47.
%t Table[n*Sum[i^MoebiusMu[i] (1 - Ceiling[n/i] + Floor[n/i]), {i, n}], {n, 80}]
%o (PARI) a(n) = n*sumdiv(n, d, d^moebius(d)); \\ _Michel Marcus_, May 25 2021
%Y Cf. A008683 (mu).
%K nonn
%O 1,2
%A _Wesley Ivan Hurt_, May 24 2021
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