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A218407
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Numbers n for which sigma(n)/n = k+2/5 with integer k.
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5
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30, 140, 2480, 6200, 40640, 297600, 997920, 64995840, 167751680, 1502582400, 42949345280, 183196016640, 687193456640, 1447428787200, 63870637017600, 326676430080000, 20797363851264000, 24871926476966400, 42981218625945600, 404918548479244800
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OFFSET
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1,1
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COMMENTS
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a(12) > 10^11. - Donovan Johnson, Oct 31 2012
a(14) > 10^12. - Giovanni Resta, Nov 04 2012
Note that there are no terms here with abundancy 7/5 (k=1). - Michel Marcus, Jun 26 2013
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LINKS
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Table of n, a(n) for n=1..20.
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FORMULA
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sigma(n)/n = k+2/5 with integer k.
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CROSSREFS
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Cf. A218406, A218408, A218427.
Sequence in context: A158462 A064495 A267904 * A347222 A229450 A124958
Adjacent sequences: A218404 A218405 A218406 * A218408 A218409 A218410
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KEYWORD
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nonn
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AUTHOR
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Zdenek Cervenka, Oct 28 2012
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EXTENSIONS
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a(8)-a(11) from Donovan Johnson, Oct 31 2012
a(12)-a(13) from Giovanni Resta, Nov 04 2012
More terms from Michel Marcus, Jun 26 2013
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STATUS
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approved
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