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A291373
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a(n) is the smallest number k such that A001065(k) = A002110(n), or 0 if no such k exists.
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0
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OFFSET
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0,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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a(5) = 1722 because sigma(1722) - 1722 = 2*3*5*7*11 = A002110(5) and 1722 is the least number with this property.
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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