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Numbers that are the sum of 2 nonzero squares in 7 or more ways.
5

%I #21 Aug 05 2021 07:31:41

%S 27625,32045,40885,45305,47125,55250,58565,60125,61625,64090,66625,

%T 67405,69745,71825,77285,78625,80665,81770,86125,87125,90610,91205,

%U 93925,94250,98345,98605,99125,99905,101065,105625,107185,110500,111605,112625

%N Numbers that are the sum of 2 nonzero squares in 7 or more ways.

%H Robert Price, <a href="/A025298/b025298.txt">Table of n, a(n) for n = 1..100</a>

%H <a href="/index/Su#ssq">Index entries for sequences related to sums of squares</a>

%t Parallelize[Select[Range[120000],Length[PowersRepresentations[#,2,2]]>6&]] (* _Harvey P. Dale_, Feb 19 2011 *)

%t nn = 112625; t = Table[0, {nn}]; lim = Floor[Sqrt[nn - 1]]; Do[num = i^2 + j^2; If[num <= nn, t[[num]]++], {i, lim}, {j, i}]; Flatten[Position[t, _?(# >= 7 &)]] (* _T. D. Noe_, Apr 07 2011 *)

%Y Cf. A025290, A025297, A025299, A025335.

%K nonn

%O 1,1

%A _David W. Wilson_