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Search: id:A064595
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| A064595 |
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Nontrivial nonunitary multiply perfect numbers: the sum of the nonunitary divisors of n is a positive multiple of n; i.e. (sigma(n) - usigma(n))/n is a positive integer. |
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+0 6
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| 24, 112, 1984, 2520, 31320, 32512, 1163160, 2208384, 3053232, 6535296, 13472928, 123165600, 134201344, 186076800, 365959296, 3456573120, 4401782352, 5517818880, 18924364800, 34359476224, 325377803520
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OFFSET
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1,1
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MATHEMATICA
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nusigma[ n_ ] := DivisorSigma[ 1, n ]-Times@@(1+Power@@#&/@FactorInteger[ n ]); For[ n=1, True, n++, v=nusigma[ n ]; If[ v>0&&Mod[ v, n ]==0, Print[ n ] ] ]
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CROSSREFS
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Cf. A048146, A064591, A064592, A064593, A064594, A064596.
Sequence in context: A101862 A103473 A162451 this_sequence A064591 A124952 A126411
Adjacent sequences: A064592 A064593 A064594 this_sequence A064596 A064597 A064598
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KEYWORD
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nonn,hard
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AUTHOR
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Dean Hickerson (dean.hickerson(AT)yahoo.com), Sep 25, 2001
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