A369909 a(n) = n * Sum_{p|n, p prime} Omega(n/p) / p.

0, 0, 0, 2, 0, 5, 0, 8, 3, 7, 0, 20, 0, 9, 8, 24, 0, 30, 0, 28, 10, 13, 0, 60, 5, 15, 18, 36, 0, 62, 0, 64, 14, 19, 12, 90, 0, 21, 16, 84, 0, 82, 0, 52, 48, 25, 0, 160, 7, 70, 20, 60, 0, 135, 16, 108, 22, 31, 0, 186, 0, 33, 60, 160, 18, 122, 0, 76, 26, 118, 0, 240, 0

Offset

1,4

Links

Table of n, a(n) for n=1..73.

Formula

a(p^k) = (k-1)*p^(k-1), for p prime and k >= 1. - Wesley Ivan Hurt, Jun 26 2024

Mathematica

Table[n*DivisorSum[n, PrimeOmega[n/#]/# &, PrimeQ[#] &], {n, 100}]

Crossrefs

Cf. A001222 (Omega), A369741, A369908.

Sequence in context: A340592 A326831 A196409 * A326830 A115333 A242689

Adjacent sequences: A369906 A369907 A369908 * A369910 A369911 A369912

Keyword

nonn,easy

Author

Wesley Ivan Hurt, Feb 05 2024

Status

approved