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A212490
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Least number m > 1 such that A000203(x)*x = m has exactly n solutions.
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3
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OFFSET
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1,1
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COMMENTS
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6 = 6.
336 = 6*28*2.
333312 = 6*28*496*2*2.
5418319872 = 6*28*496*8128*2*2*2.
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REFERENCES
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R. K. Guy, Unsolved Problems in Theory of Numbers, Springer-Verlag, Third Edition, 2004, B11.
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LINKS
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Table of n, a(n) for n=1..5.
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EXAMPLE
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For n=3, 333312 has exactly 3 solutions: sigma(434)*434 = 333312, sigma(372)*372 = 333312, and sigma(336)*336 = 333312; therefore a(3) = 333312.
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CROSSREFS
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Cf. A212489, A212327, A212373.
Sequence in context: A210769 A003031 A144849 * A047941 A229501 A289738
Adjacent sequences: A212487 A212488 A212489 * A212491 A212492 A212493
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KEYWORD
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nonn,more
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AUTHOR
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Naohiro Nomoto, May 18 2012
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EXTENSIONS
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a(5) from Donovan Johnson, May 20 2012
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STATUS
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approved
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