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A354073
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Multiply-perfect numbers that are the sum of the divisors of some number.
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2
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1, 6, 28, 120, 496, 672, 30240, 32760, 523776, 2178540, 23569920, 33550336, 45532800, 142990848, 459818240, 1379454720, 1476304896
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OFFSET
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1,2
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COMMENTS
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Conjecture: 8128 is only multiply-perfect number that is not in this sequence.
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LINKS
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EXAMPLE
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Number 28 is in the sequence because sigma(12) = 28.
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PROG
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(Magma) Set(Sort([&+Divisors(m): m in [1..10^7] | IsIntegral(&+Divisors(&+Divisors(m)) / &+Divisors(m))]))
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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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STATUS
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approved
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