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%I #13 Feb 01 2022 00:57:30
%S 0,9,41,81,146,194,306,369,425,594,689,866,1109,1154,1154,1361,1634,
%T 1781,1889,2141,2609,2609,3366,3366,3449,3449,3506,4241,4289,4826,
%U 5066,5381,5561,5561,6254,7229,7829,8069,8069,8126,8609,8774,8774
%N Smallest number that is the sum of 3 squares in at least n ways.
%H T. D. Noe, <a href="/A000451/b000451.txt">Table of n, a(n) for n = 1..200</a>
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>
%t nn = 100; lim = nn^2; t = Table[0, {lim}]; Do[k = x^2 + y^2 + z^2; If[0 < k <= lim, t[[k]]++], {x, 0, nn}, {y, x, nn}, {z, y, nn}]; u = Union[t]; c = Complement[Range[u[[-1]]], u]; If[c == {}, mx = u[[-1]], mx = c[[1]] - 1]; Join[{0}, Flatten[Table[Position[t, _?(# >= n &), 1, 1], {n, 2, mx}]]] (* _T. D. Noe_, Jun 20 2012 *)
%K nonn
%O 1,2
%A _N. J. A. Sloane_
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