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Search: id:A136528
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| A136528 |
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a(n) = the highest possible number of positive divisors of the sum of any two distinct positive divisors of n. |
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+0
2
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| 2, 3, 4, 4, 4, 4, 6, 6, 6, 6, 6, 4, 5
(list; graph; listen)
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OFFSET
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2,1
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COMMENT
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There are d(n)*(d(n)-1)/2 sums of pairs of distinct positive divisors of n, where d(n) = number of positive divisors of n.
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LINKS
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Leroy Quet, Home Page (listed in lieu of email address)
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EXAMPLE
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The positive divisors of 6 are 1,2,3,6. Letting d(m) = the number of positive divisors of m: d(1+2)=2; d(1+3)=3; d(1+6)=2; d(2+3)=2; d(2+6)=4; d(3+6)=3. The maximum of these values is 4, so a(6) = 4.
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CROSSREFS
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Cf. A136529.
Adjacent sequences: A136525 A136526 A136527 this_sequence A136529 A136530 A136531
Sequence in context: A029106 A064004 A087827 this_sequence A130242 A130245 A087793
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KEYWORD
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more,nonn
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AUTHOR
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Leroy Quet Jan 03 2008
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