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A180164
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The sum of the two numbers in an amicable pair, A002025(n) + A002046(n).
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14
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504, 2394, 5544, 10584, 12600, 21600, 26880, 35712, 139104, 133920, 138240, 157248, 168480, 224640, 262080, 245520, 294840, 311040, 348192, 357120, 388800, 399168, 645624, 698544, 749952, 756000, 892800, 955206, 1017792, 1048320
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OFFSET
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1,1
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COMMENTS
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This sequence initially shares many terms with A161005 because small amicable pairs are sometimes consecutive terms in the sorted list of amicable numbers, A063990.
This sequence is sorted by the smaller (abundant) member from A002025, so a(n) is not increasing. - Jeppe Stig Nielsen, Jan 27 2015
It is not known if a(n) is always even (see Hagis links). - Jeppe Stig Nielsen, Jan 31 2015
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LINKS
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Eric W. Weisstein's World of Mathematics, Pair Sum.
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FORMULA
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EXAMPLE
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MATHEMATICA
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s[n_] := DivisorSigma[1, n]-n; smallAmicableQ[n_] := Module[{b=s[n]}, n<b && s[b]==n]; a=Select[Range[10^6], smallAmicableQ]; Table[n+s[n], {n, a}]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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