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 A125491 Amicable triples: numbers such that sigma(x) = sigma(y) = sigma(z) = x+y+z, x
 2016, 9504, 22200, 31284, 41412, 40068, 40608, 43890, 54990, 52290, 53676, 69030, 69420, 77688, 83720, 84252, 82236, 80892, 87750, 93870, 96048, 97416, 107040, 129108, 129504, 137610, 127908, 156450, 144936, 152520 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Giovanni Resta computed these terms. As stated, we first order by common sigma value. When the common value of sigma is the same for several triples, these are then sorted (ascending) by the smallest member. When the smallest members also agree, we go on to the second smallest members, and so on, lexicographically. - John Cerkan, Jun 18 2016 LINKS John Cerkan, Table of n, a(n) for n = 1..10000 [Terms 1 through 1000 were computed by Donovan Johnson] EXAMPLE 2016 is in the sequence since sigma(1980) = sigma(2016) = sigma(2556) = 6552 = 1980 + 2016 + 2556. - Michael B. Porter, Jun 29 2016 CROSSREFS Cf. A125490, A125492, A137231 (x+y+z). Cf. A000203 (sigma function). Sequence in context: A076666 A189188 A076582 * A166818 A166800 A223216 Adjacent sequences:  A125488 A125489 A125490 * A125492 A125493 A125494 KEYWORD nonn AUTHOR Yasutoshi Kohmoto, Dec 11 2006 EXTENSIONS Definition corrected by N. J. A. Sloane, Nov 27 2008 a(13)-a(30) from Donovan Johnson, Apr 14 2010 STATUS approved

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Last modified December 10 17:20 EST 2018. Contains 318049 sequences. (Running on oeis4.)