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Numbers x such that there exist a pair y, n with x < y, x != n and y != n that makes {x,y,n,n} an amicable multiset.
3

%I #19 Jul 27 2016 21:55:22

%S 695520,753480,1113840,1136520,1784160,2313360,2898720,3140280,

%T 3865680,3960600,4272840,4500720,4626720,6126120,6167700,7197960,

%U 7442820,7731360,8177400,8498700,8784720,8828820,8920800,8966160,9124920,9232860,9664200,9729720

%N Numbers x such that there exist a pair y, n with x < y, x != n and y != n that makes {x,y,n,n} an amicable multiset.

%C We call the multiset {x,y,n,n} amicable iff sigma(x) = sigma(y) = sigma(n) = x+y+n+n. For the n values, see A273969. For the y values, see A273971.

%C If the condition x<y were dropped, the terms from A259306 would also belong here.

%H John Cerkan, <a href="/A273970/b273970.txt">Table of n, a(n) for n = 1..8060</a>

%H John Cerkan, <a href="/A273970/a273970.py.txt">Python code</a>

%e sigma(695520) = sigma(803040) = sigma(702240) = 695520 + 803040 + 702240 + 702240.

%Y Cf. A259302, A259303, A259304, A259305, A259306, A273969, A273971.

%K nonn

%O 1,1

%A _John Cerkan_, Jul 17 2016