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A186963
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Number of prime factors in the expansion of the infinitary perfect number A007357(n) over distinct terms of A050376
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0
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2, 2, 2, 3, 4, 3, 4, 5, 4, 4, 6, 5, 6, 7, 6, 7, 6
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OFFSET
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1,1
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COMMENTS
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The total number of factors in the decomposition of A007357(n) in terms of A050376 is A187043(n). The subset of factors which are ordinary primes are counted here.
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LINKS
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FORMULA
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EXAMPLE
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The unique expansion of A007357(2)= 60 as a product of terms of A050376 is 3*4*5. Two of these factors, namely 3 and 5, are primes (A000040), so a(2)=2.
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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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