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%I #3 Apr 19 2016 01:10:16
%S 3,45,1512,51408,66528,85500,185976,6323184,8182944,11442816,43023600,
%T 318041100,1407466368,5881607424,22350712320,723437713152,
%U 183348802920960
%N Consider numbers x,y,z such that UnitarySigma(x) = UnitarySigma(y) = UnitarySigma(z) = 4*(x*y*z)^(1/2)/( x^(1/2) + y^(1/2) + z^(1/2)), x<=y<=z . Sequence gives x .
%C a(6) : x=y, y<z
%C a(11) : x=y, y<z
%C a(12) : x<y, y=z
%K nonn
%O 1,1
%A _Yasutoshi Kohmoto_, Feb 21 2009