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A345355
a(n) = Sum_{p|n, p prime} p^omega(n/p).
3
0, 1, 1, 2, 1, 5, 1, 2, 3, 7, 1, 7, 1, 9, 8, 2, 1, 11, 1, 9, 10, 13, 1, 7, 5, 15, 3, 11, 1, 38, 1, 2, 14, 19, 12, 13, 1, 21, 16, 9, 1, 62, 1, 15, 14, 25, 1, 7, 7, 27, 20, 17, 1, 11, 16, 11, 22, 31, 1, 42, 1, 33, 16, 2, 18, 134, 1, 21, 26, 78, 1, 13, 1, 39, 28, 23, 18, 182
OFFSET
1,4
FORMULA
a(p) = 1 for p prime.
EXAMPLE
a(30) = Sum_{p|30} p^omega(30/p) = 2^omega(15) + 3^omega(10) + 5^omega(6) = 2^2 + 3^2 + 5^2 = 38.
MATHEMATICA
Table[Sum[k^PrimeNu[n/k] (PrimePi[k] - PrimePi[k - 1]) (1 - Ceiling[n/k] + Floor[n/k]), {k, n}], {n, 100}]
PROG
(PARI) a(n) = my(f=factor(n)); sum(k=1, #f~, f[k, 1]^omega(n/f[k, 1])); \\ Michel Marcus, Jun 16 2021
CROSSREFS
Cf. A001221 (omega).
Sequence in context: A351954 A353577 A200778 * A132601 A047818 A055972
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jun 15 2021
STATUS
approved