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A059047
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Numbers x such that sigma(x)-x divides x-1, other than prime powers.
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3
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77, 611, 1073, 2033, 5293, 6031, 9983, 13969, 15947, 23489, 25241, 40301, 49901, 50249, 51101, 56759, 65017, 71677, 85079, 97217, 97783, 98099, 99101, 131237, 142091, 160133, 165101, 180767, 189281, 210367, 213053, 228719, 259741, 303239
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OFFSET
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1,1
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COMMENTS
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Primes and prime powers (A000961) also satisfy this equation. A059046 is the union of A000961 and A059047. These numbers are related to hyperperfect numbers (A034897) in the cited paper by te Riele.
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LINKS
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EXAMPLE
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For x=77, sigma(77)=96, 96-77=19, which divides 77-1.
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PROG
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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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