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A207639 Squares that can be written as a sum of 3 distinct nonzero squares in more than one way. 2

%I #7 Aug 11 2015 01:14:58

%S 225,361,441,529,625,729,841,900,961,1089,1225,1369,1444,1521,1681,

%T 1764,1849,2025,2116,2209,2401,2500,2601,2809,2916,3025,3249,3364,

%U 3481,3600,3721,3844,3969,4225,4356,4489,4761,4900,5041,5329,5476,5625,5776,5929

%N Squares that can be written as a sum of 3 distinct nonzero squares in more than one way.

%t t = Sort[Select[Flatten[Table[x^2 + y^2 + z^2, {x, 400}, {y, x + 1, 400}, {z, y + 1, 400}]], # < 160006 && IntegerQ[Sqrt[#]] &]];

%t f1[l_] := Module[{t = {}}, Do[If[l[[n]] != l[[n + 1]] && l[[n]] != l[[n - 1]], AppendTo[t, l[[n]]]], {n, Length[l] - 1}]; t];

%t s1 = Join[{First[t]}, f1[t]];

%t Complement[t, s1]

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Feb 19 2012

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Last modified April 19 23:40 EDT 2024. Contains 371798 sequences. (Running on oeis4.)