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A346612
Moebius transform of A019554.
2
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
OFFSET
1,3
LINKS
N. J. A. Sloane, Transforms.
FORMULA
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
MATHEMATICA
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 *)
PROG
(PARI) a(n) = sumdiv(n, d, moebius(n/d)*d/core(d, 1)[2]); \\ Michel Marcus, Aug 18 2021
CROSSREFS
KEYWORD
nonn,mult,easy
AUTHOR
N. J. A. Sloane, Aug 18 2021
STATUS
approved