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Difference between the larger and smaller terms of the n-th amicable pair (x,y) given in A259933.
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%I #16 Aug 06 2016 14:04:09

%S 64,26,304,544,136,112,2310,1120,64,4050,13064,18018,8980,23670,784,

%T 17550,11512,26420,4480,4576,18064,5720,84544,81304,110852,43184,

%U 17888,17150,11680,3510,69296,76144,9328,67072,76592,115592,70592,61110,21712,82768

%N Difference between the larger and smaller terms of the n-th amicable pair (x,y) given in A259933.

%C Each term represents the length of an interval (x,y), where x (A260086) and y (A260087) form a pair of amicable numbers (A259933). The midpoint and radius of each interval can be found in A275316 and A275470, respectively.

%C Each term will be even as long as there does not exist an amicable pair where x and y have opposite parity.

%C This sequence is a rearrangement of A066539 (which is based on A002025, A002046, and A259180). The first ten indices for which a(n) does not equal A066539(n) are n = 9, 10, 11, 15, 16, 33, 34, 35, 41, 42.

%H Timothy L. Tiffin, <a href="/A275469/b275469.txt">Table of n, a(n) for n = 1..142</a>

%H VaxaSoftware, <a href="http://www.vaxasoftware.com/doc_eduen/mat/numamigos_eng.pdf">List of amicable numbers from 1 to 20,000,000</a> [142 pairs].

%F a(n) = A260087(n) - A260086(n).

%e a(1) = 284 - 220 = 64, a(2) = 1210 - 1184 = 26, and a(3) = 2924 - 2620 = 304.

%Y Cf. A002025, A002046, A066539, A259180, A259933, A260086, A260087, A275316, A275470.

%K nonn

%O 1,1

%A _Timothy L. Tiffin_, Jul 28 2016