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A346612
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Moebius transform of A019554.
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2
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1, 1, 2, 0, 4, 2, 6, 2, 0, 4, 10, 0, 12, 6, 8, 0, 16, 0, 18, 0, 12, 10, 22, 4, 0, 12, 6, 0, 28, 8, 30, 4, 20, 16, 24, 0, 36, 18, 24, 8, 40, 12, 42, 0, 0, 22, 46, 0, 0, 0, 32, 0, 52, 6, 40, 12, 36, 28, 58, 0, 60, 30, 0, 0, 48, 20, 66, 0, 44, 24, 70, 0, 72, 36, 0, 0, 60, 24, 78, 0, 0
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OFFSET
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1,3
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LINKS
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FORMULA
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Multiplicative with a(p^e) = 0 if e is even, and p^((e+1)/2) - p^((e-1)/2) if e is odd. - Amiram Eldar, Aug 19 2021
Sum_{k=1..n} a(k) ~ c * n^2, where c = 18*zeta(3)/Pi^4 = 0.222125... . - Amiram Eldar, Nov 18 2022
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MATHEMATICA
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f[p_, e_] := If[EvenQ[e], 0, p^((e + 1)/2) - p^((e - 1)/2)]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Aug 19 2021 *)
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PROG
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(PARI) a(n) = sumdiv(n, d, moebius(n/d)*d/core(d, 1)[2]); \\ Michel Marcus, Aug 18 2021
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CROSSREFS
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KEYWORD
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nonn,mult,easy
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AUTHOR
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STATUS
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approved
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