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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
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3, 12, 234, 1080, 6048, 6552, 435708, 4713984, 18506880, 36197280, 275890944, 299980800, 4138364160, 13286744064, 17827568640, 30600708096
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| a(17) > 2*10^11. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), May 26 2009]
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EXAMPLE
| 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
| 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 * A102945 A132515 A036300
Adjacent sequences: A160317 A160318 A160319 * A160321 A160322 A160323
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KEYWORD
| nonn
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AUTHOR
| J.C. Klein (hklein(AT)planet.nl), May 08 2009
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EXTENSIONS
| a(11)-a(16) from Donovan Johnson (donovan.johnson(AT)yahoo.com), May 26 2009
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