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A153078
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Number of values of m such that sigma(m) = A002110(n) where A002110(n) is the product of the first n primes.
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2
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0, 1, 1, 2, 2, 5, 2, 4, 5, 3, 7, 5, 10, 2, 8, 4, 5, 6, 11, 32, 42, 68, 24, 87
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OFFSET
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1,4
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LINKS
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FORMULA
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EXAMPLE
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a(10) = 3 because 2388809736, 3450503048 and 3696967556 are the only numbers with a sigma value = A002110(10). A002110(10) = 6469693230 = 2*3*5*7*11*13*17*19*23*29.
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CROSSREFS
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KEYWORD
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nonn,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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