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A055488
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Smallest number x such that sum of divisors of x is n!.
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4
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5, 14, 54, 264, 1560, 10920, 97440, 876960, 10263240, 112895640, 1348827480, 18029171160, 264370186080, 3806158356000, 62703141621120, 1128159304272000, 20422064875212000, 404757215566704000, 8208550091549808000, 177650747421074928000
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OFFSET
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3,1
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COMMENTS
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For n = 1, a(1) = 1; for n = 2, there is no solution.
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REFERENCES
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R. K. Guy (1981): Unsolved Problems In Number Theory, B39.
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LINKS
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FORMULA
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EXAMPLE
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For n = 6 the 15 solutions are as follows: {264,270,280,354,376,406,418,435,459,478,537,623,649,667,719}
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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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a(13), a(14) from Vim Wenders, Nov 06 2006, Jan 12 2007
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STATUS
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approved
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