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A069812
a(n) = Sum_{k=1..n} (bigomega(k)-omega(k)).
2
0, 0, 0, 1, 1, 1, 1, 3, 4, 4, 4, 5, 5, 5, 5, 8, 8, 9, 9, 10, 10, 10, 10, 12, 13, 13, 15, 16, 16, 16, 16, 20, 20, 20, 20, 22, 22, 22, 22, 24, 24, 24, 24, 25, 26, 26, 26, 29, 30, 31, 31, 32, 32, 34, 34, 36, 36, 36, 36, 37, 37, 37, 38, 43, 43, 43, 43, 44, 44, 44, 44, 47, 47, 47, 48
OFFSET
1,8
LINKS
FORMULA
a(n) ~ A136141 * n, where A136141 = 0.773156669... - Vaclav Kotesovec, Sep 01 2019
G.f.: (1/(1 - x)) * Sum_{p prime, k>=2} x^(p^k)/(1 - x^(p^k)). - Ilya Gutkovskiy, Sep 03 2019
MATHEMATICA
Accumulate[Table[PrimeOmega[n]-PrimeNu[n], {n, 80}]] (* Harvey P. Dale, Oct 10 2015 *)
PROG
(PARI) lista(nmax) = {my(s = 0, e); for(n = 1, nmax, e = factor(n)[, 2]; s += vecsum(e) - #e; print1(s, ", ")); } \\ Amiram Eldar, Sep 17 2024
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Apr 30 2002
STATUS
approved