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A195093
Numbers k such that (number of prime factors of k counted with multiplicity) less (number of distinct prime factors of k) = 9.
12
1024, 3072, 4608, 5120, 6912, 7168, 10368, 11264, 12800, 13312, 15360, 15552, 17408, 19456, 21504, 23040, 23328, 23552, 25088, 29696, 31744, 32000, 32256, 33792, 34560, 34992, 35840, 37888, 38400, 39936, 41984, 44032, 48128, 48384
OFFSET
1,1
COMMENTS
The asymptotic density of this sequence is (6/Pi^2) * Sum_{k>=1} f(a(k)) = 0.0007396..., where f(k) = A112526(k) * Product_{p|k} p/(p+1). - Amiram Eldar, Sep 24 2024
FORMULA
A046660(a(n)) = 9. - Reinhard Zumkeller, Nov 29 2015
MATHEMATICA
Select[Range[50000], PrimeOmega[#]-PrimeNu[#]==9&]
PROG
(PARI) is(n)=bigomega(n)-omega(n)==9 \\ Charles R Greathouse IV, Sep 14 2015
(Haskell)
a195093 n = a195093_list !! (n-1)
a195093_list = filter ((== 9) . a046660) [1..]
-- Reinhard Zumkeller, Nov 29 2015
KEYWORD
nonn,easy
AUTHOR
Harvey P. Dale, Sep 08 2011
STATUS
approved