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%I #25 Jul 02 2016 01:59:03
%S 1980,9180,21168,23940,37380,38940,38940,39480,46368,47124,53088,
%T 57420,66720,67860,69720,73320,75180,77490,72072,86040,93456,96660,
%U 92820,100980,100980,112140,118944,121800,139080,141372
%N Amicable triples: numbers such that sigma(x) = sigma(y) = sigma(z) = x+y+z, x<y<z. We order these triples according to the common value of sigma. Sequence gives x numbers.
%C G. Resta computed these terms.
%C 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
%H John Cerkan, <a href="/A125490/b125490.txt">Table of n, a(n) for n = 1..10000</a> [Terms 1 through 1000 were computed by Donovan Johnson]
%e 1980 is in the sequence since sigma(1980) = sigma(2016) = sigma(2556) = 6552 = 1980 + 2016 + 2556. - _Michael B. Porter_, Jun 29 2016
%Y Cf. A125491, A125492, A137231 (x+y+z).
%Y Cf. A036471 - A036474 and A116148 (amicable quadruples).
%Y Cf. A233553 for amicable 5-tuples.
%Y Cf. A000203 (sigma function).
%K nonn
%O 1,1
%A _Yasutoshi Kohmoto_, Dec 11 2006
%E Definition corrected by _N. J. A. Sloane_, Nov 27 2008
%E a(13)-a(30) from _Donovan Johnson_, Apr 14 2010
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