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 A125491 Amicable triples: numbers such that sigma(x) = sigma(y) = sigma(z) = x+y+z, x

%I

%S 2016,9504,22200,31284,41412,40068,40608,43890,54990,52290,53676,

%T 69030,69420,77688,83720,84252,82236,80892,87750,93870,96048,97416,

%U 107040,129108,129504,137610,127908,156450,144936,152520

%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 y numbers.

%C _Giovanni 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="/A125491/b125491.txt">Table of n, a(n) for n = 1..10000</a> [Terms 1 through 1000 were computed by Donovan Johnson]

%e 2016 is in the sequence since sigma(1980) = sigma(2016) = sigma(2556) = 6552 = 1980 + 2016 + 2556. - _Michael B. Porter_, Jun 29 2016

%Y Cf. A125490, A125492, A137231 (x+y+z).

%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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Last modified May 23 13:32 EDT 2019. Contains 323514 sequences. (Running on oeis4.)