A207638 Squares that can be written as a sum of 3 distinct nonzero squares in no more than one way.

49, 81, 121, 169, 196, 289, 324, 484, 676, 784, 1156, 1296, 1936, 2704, 3136, 4624, 5184, 7744, 10816, 12544, 18496, 20736, 30976, 43264, 50176, 73984, 82944, 123904

Offset: 1

Author

Vladimir Joseph Stephan Orlovsky, Feb 19 2012

Keywords

• nonn

Programs

Mathematica

t = Sort[Select[Flatten[Table[x^2 + y^2 + z^2, {x, 400}, {y, x + 1, 400}, {z, y + 1, 400}]], # < 160006 && IntegerQ[Sqrt[#]] &]];
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];
s1 = Join[{First[t]}, f1[t]]