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A073329
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a(n) is the n-th number to have n distinct prime factors.
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6
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2, 10, 60, 420, 4290, 53130, 903210, 17687670, 406816410, 11125544430, 338431883790, 11833068917670, 457077357006270, 20384767656323070, 955041577211912190, 49230430891074322890, 2740956243836856315270, 168909608387276001835590, 11054926927790884163355330
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 2 because 2 is the first number to have one prime factor.
a(2) = 10 because 10 is the second number to have two prime factors; 6 is the first.
a(3) = 60 = 2*2*3*5 because 60 is the third number to have three prime factors (2,3,5); 30 is the first and 42 is the second.
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CROSSREFS
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a(n) is last term in n-th row of A048692.
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Corrected from a(9) onwards by T. D. Noe, Dec 01 2004
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STATUS
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approved
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