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A211677
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First number k whose value of sigma(k)/k appears n times.
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2
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OFFSET
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1,2
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COMMENTS
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The values of sigma(k)/k are 1, 2, 2, 8/3, 8/3, 96/35, 32/9, 32/9, 32/7. Note that these values are nondecreasing. Is that always the case? In the table below, all numbers in the same row are friendly to each other.
For n>1, these are the smallest numbers to appear consecutively (n-1) times in A050973. - Michel Marcus, Jan 28 2014
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LINKS
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EXAMPLE
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These are the values of k such that sigma(k)/k appears n times:
n k values
1: 1
2: 6, 28
3: 6, 28, 496
4: 84, 270, 1488, 1638
5: 84, 270, 1488, 1638, 24384
6: 210, 17360, 43400, 284480, 2229500, 2886100
7: 3780, 66960, 167400, 406224, 1097280, 6656832, 13035330
8: 3780, 66960, 167400, 406224, 1097280, 6656832, 13035330, 29410290
9: 164989440, 270138960, 318729600, 326781000, 481572000, 623397600, 675347400, 995248800, 4426793280 - Donovan Johnson, Aug 06 2012
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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