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A161005
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Sums of adjacent amicable numbers, a(n) = A063990(2n-1) + A063990(2n).
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9
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504, 2394, 5544, 10584, 12600, 21600, 26880, 35712, 129948, 134087, 140760, 155834, 176363, 222750, 245520, 263970, 283974, 321906, 348128, 357184, 382092, 405876, 589160, 675958, 755008, 829994, 892800, 955206, 1017792, 1048320
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OFFSET
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1,1
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COMMENTS
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Warning: The numbers being summed will not always belong to the same amicable pair. See A180164 for the sums of amicable pairs. - Jeppe Stig Nielsen, Jan 27 2015
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LINKS
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EXAMPLE
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a(1) = 504 = 220 + 284.
a(2) = 2394 = 1184 + 1210.
a(3) = 5544 = 2620 + 2694.
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MATHEMATICA
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s[n_] := DivisorSigma[1, n] - n;
AmicableNumberQ[n_] := If[Nest[s, n, 2] == n && ! s[n] == n, True, False];
a = Select[Range[10^6], AmicableNumberQ[ # ] &];
Table[a[[n + 1]] + a[[n]], {n, 1, Length[a], 2}]
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CROSSREFS
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KEYWORD
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nonn,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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