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A332683
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a(n) = Sum_{k=1..n, gcd(n, k) = 1} ceiling(n/k).
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0
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1, 2, 5, 6, 12, 8, 20, 15, 23, 18, 37, 19, 47, 28, 38, 37, 66, 31, 76, 41, 61, 52, 96, 44, 96, 63, 89, 66, 129, 49, 141, 84, 109, 88, 129, 72, 176, 101, 132, 95, 198, 77, 210, 116, 142, 129, 232, 99, 226, 122, 186, 144, 269, 114, 232, 149, 214, 169, 305, 110
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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a(n) = Sum_{d|n} mu(n/d) * A006590(d).
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MATHEMATICA
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Table[Sum[Boole[GCD[n, k] == 1] Ceiling[n/k], {k, 1, n}], {n, 1, 60}]
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PROG
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(PARI) a(n) = sum(k=1, n, if (gcd(n, k) == 1, ceil(n/k))); \\ Michel Marcus, Feb 21 2020
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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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