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Search: id:A160320
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| A160320 |
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Numbers n for which sigma(n)/n=k+1/3 with integer k |
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+0
1
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| 3, 12, 234, 1080, 6048, 6552, 435708, 4713984, 18506880, 36197280, 275890944, 299980800, 4138364160, 13286744064, 17827568640, 30600708096
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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a(17) > 2*10^11. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), May 26 2009]
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EXAMPLE
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a(1)=3 since sigma(3)/3=(1+3)/3=1+1/3
a(2)=12 since sigma(12)/12=(1+2+3+4+6+12)/12=28/12=7/3=2+1/3
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CROSSREFS
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Cf. A160321 Numbers n for which sigma(n)/n=k+2/3 Cf. A159907 Numbers n for which sigma(n)/n=k+1/2
Sequence in context: A120606 A089428 A063801 this_sequence A102945 A132515 A036300
Adjacent sequences: A160317 A160318 A160319 this_sequence A160321 A160322 A160323
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KEYWORD
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nonn
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AUTHOR
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J.C. Klein (hklein(AT)planet.nl), May 08 2009
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EXTENSIONS
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a(11)-a(16) from Donovan Johnson (donovan.johnson(AT)yahoo.com), May 26 2009
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