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A123528
Numerator of average of prime factors of n.
16
2, 3, 2, 5, 5, 7, 2, 3, 7, 11, 7, 13, 9, 4, 2, 17, 8, 19, 3, 5, 13, 23, 9, 5, 15, 3, 11, 29, 10, 31, 2, 7, 19, 6, 5, 37, 21, 8, 11, 41, 4, 43, 5, 11, 25, 47, 11, 7, 4, 10, 17, 53, 11, 8, 13, 11, 31, 59, 3, 61, 33, 13, 2, 9, 16, 67, 7, 13, 14, 71, 12, 73, 39, 13, 23, 9, 6, 79, 13, 3, 43, 83, 7
OFFSET
2,1
LINKS
FORMULA
a(n) = sopfr(n) / bigomega(n) = A001414(n) / A001222(n).
EXAMPLE
12 = 2 * 2 * 3, so a(12) = (2 + 2 + 3) / 3 = 7/3.
Sequence of fractions starts 2/1, 3/1, 2/1, 5/1, 5/2, 7/1, 2/1, 3/1, 7/2, 11/1, 7/3.
MATHEMATICA
f[n_] := Plus @@ Times @@@ FactorInteger@n; f[1] = 0; Numerator[ Table[ f[n]/PrimeOmega[n], {n, 2, 50}]] (* G. C. Greubel, Oct 14 2017 *)
CROSSREFS
KEYWORD
frac,nonn
AUTHOR
STATUS
approved