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%I #16 Oct 22 2017 16:00:16
%S 64,26,304,544,136,112,2310,1120,13064,64,4050,18018,8980,23670,17550,
%T 784,11512,26420,4480,4576,18064,5720,84544,81304,110852,43184,17888,
%U 17150,11680,3510,69296,76144,67072,76592,9328,115592,70592,61110,21712
%N Difference between larger and smaller terms of n-th amicable pair.
%C Values are sorted along increasing A002025. - _R. J. Mathar_, Jul 19 2009, Jul 23 2009
%D For references see A002025.
%H Michael De Vlieger, <a href="/A066539/b066539.txt">Table of n, a(n) for n = 1..415523</a>
%F a(n) = A002046(n) - A002025(n).
%F a(n) = A259180(2n) - A259180(2n-1). - _Omar E. Pol_, Oct 22 2017
%e a(7) = 2310 because the 7th pair of amicable numbers is 12285 and 14595; and 14595 - 12285 = 2310.
%t With[{s = PositionIndex@Array[DivisorSigma[1, #] &, 10^6]}, Flatten@ Map[Differences, Apply[Join, Map[Function[n, Select[Subsets[Lookup[s, n], {2}], Total@ # == n &]], Sort@ Select[Keys@ s, Length@ Lookup[s, #] > 1 &]]]]] (* _Michael De Vlieger_, Oct 22 2017 *)
%Y Cf. A002025, A002046, A063990, A259180 (amicable pairs).
%K nonn
%O 1,1
%A Robert A. Stump (bee_ess107(AT)yahoo.com), Jan 06 2002
%E Sorted on smaller term for alignment with A002046 and A002025. - _R. J. Mathar_, Jul 19 2009
%E A-number in comment corrected by _R. J. Mathar_, Jul 23 2009
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