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A156236
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Smallest pentagonal number with n distinct prime factors.
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4
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5, 12, 70, 210, 11310, 145860, 1560090, 23130030, 2491434660, 200736225690, 1906748513670, 281993526895080, 9427390580377770, 904832960818356570, 117584828859645537390, 2928413909631253063020, 400579656276180828206760
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(9) = 2491434660 = 2^2*3*5*11*13*17*19*29*31. 2491434660 is the smallest pentagonal number with 9 distinct prime factors.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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