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A344033
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a(n) = n * Sum_{d|n} d^mu(n/d).
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0
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1, 6, 12, 22, 30, 47, 56, 82, 93, 117, 132, 197, 182, 219, 248, 306, 306, 419, 380, 487, 472, 519, 552, 773, 655, 717, 786, 905, 870, 1240, 992, 1154, 1136, 1209, 1272, 1697, 1406, 1503, 1576, 1927, 1722, 2322, 1892, 2125, 2258, 2187, 2256, 2981, 2457, 2857, 2672, 2927
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OFFSET
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1,2
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COMMENTS
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If p is prime, a(p) = p * Sum_{d|p} d^mu(p/d) = p * (1 + p^1) = p * (p + 1).
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LINKS
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EXAMPLE
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a(4) = 4 * Sum_{d|4} d^mu(4/d) = 4 * (1^0 + 2^(-1) + 4^1) = 22.
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MATHEMATICA
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Table[n*Sum[i^MoebiusMu[n/i] (1 - Ceiling[n/i] + Floor[n/i]), {i, n}], {n, 80}]
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PROG
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(PARI) a(n) = n*sumdiv(n, d, d^moebius(n/d)); \\ Michel Marcus, May 25 2021
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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