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%I #15 Jun 02 2017 10:39:02
%S 325,425,625,650,725,845,850,925,1025,1250,1300,1325,1445,1450,1525,
%T 1690,1700,1825,1850,2050,2225,2425,2500,2525,2600,2650,2725,2825,
%U 2873,2890,2900,2925,3050,3125,3380,3400,3425,3650,3700,3725,3757,3825,3925,4100
%N Numbers that are the sum of 2 squares in exactly 3 ways.
%H T. D. Noe, <a href="/A000443/b000443.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%t nn = 70; lim = nn^2; t = Table[0, {lim}]; Do[k = x^2 + y^2; If[0 < k <= lim, t[[k]]++], {x, 0, nn}, {y, x, nn}]; Flatten[Position[t, 3]] (* _T. D. Noe_, Jun 20 2012 *)
%t Select[Range[4500],Length[PowersRepresentations[#,2,2]]==3&] (* _Harvey P. Dale_, Jun 02 2017 *)
%K nonn
%O 1,1
%A _N. J. A. Sloane_ and J. C. Lagarias (lagarias(AT)umich.edu)
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