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A244063
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Number of prime factors (with multiplicity) of the number of distinct prime factors of n; a(n) = Omega(omega(n)).
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1
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0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1
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OFFSET
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2
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COMMENTS
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This sequence is not the same as A143731 and first departs from it when n = 210. The characteristic function A143731(210)=1, while a(210)=2. This is because 210 is the smallest number with 4 distinct prime factors (210 = 2*3*5*7) and 4 is the smallest composite number. Thus, Omega(omega(210)) = Omega(4) = 2.
The records for this sequence are at 2, 6, 210, 9699690, 32589158477190044730, ..., the products of the first 2^n primes. - Charles R Greathouse IV, Sep 14 2015
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LINKS
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FORMULA
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MATHEMATICA
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Table[PrimeOmega[PrimeNu[n]], {n, 2, 100}]
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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