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A074844
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Largest difference between consecutive divisors of n is equal to the sum of divisors of n except 1 and n.
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1
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OFFSET
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1,1
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COMMENTS
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If p = 5^k - 2 is a prime > 3, then 3*p*(p+2)/5 is in this sequence (see A109080). - Charlie Neder, Oct 13 2018
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LINKS
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EXAMPLE
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The divisors of 345 are [1, 3, 5, 15, 23, 69, 115, 345] and the largest difference between consecutive divisors is 345-115 = 230; the sum of divisors except 1 and 345 are 3+5+15+23+69+115 = 230.
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MAPLE
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with(numtheory): a:=proc(n) local div: div:=divisors(n): if max(seq(div[j]-div[j-1], j=2..tau(n)))=sigma(n)-1-n then n else fi end: seq(a(n), n=1..100000); # Emeric Deutsch, Aug 04 2005
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CROSSREFS
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KEYWORD
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nonn,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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