A345355 a(n) = Sum_{p|n, p prime} p^omega(n/p).

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

Links

Antti Karttunen, Table of n, a(n) for n = 1..20000

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), A369744.

Cf. also A369741, A369907.

Sequence in context: A351954 A353577 A200778 * A132601 A047818 A378783

Adjacent sequences: A345352 A345353 A345354 * A345356 A345357 A345358

Keyword

nonn

Author

Wesley Ivan Hurt, Jun 15 2021

Status

approved