A211648 Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2=3n.

0, 1, 3, 3, 1, 0, 3, 6, 3, 4, 6, 6, 3, 0, 6, 6, 1, 6, 12, 6, 0, 0, 12, 12, 3, 7, 6, 12, 6, 0, 12, 6, 3, 9, 6, 12, 4, 0, 12, 12, 6, 6, 18, 18, 6, 0, 12, 12, 3, 7, 15, 15, 0, 0, 12, 12, 6, 15, 18, 6, 6, 0, 18, 24, 1, 12, 15, 18, 6, 0, 12, 12, 12, 12, 18, 15, 6, 0, 24, 18, 0, 13, 18

Offset: 0

Author

Clark Kimberling, Apr 18 2012

Keywords

• nonn

Comments

For a guide to related sequences, see A211422.

Crossrefs

Cf. A211422.

Programs

Mathematica

t = Compile[{{n, _Integer}}, Module[{s = 0},
    (Do[If[w^2 + x^2 + y^2 == 3 n, s = s + 1],
        {w, 1, #}, {x, 1, #}, {y, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 100]]  (* A211648 *)
(* Peter J. C. Moses, Apr 13 2012 *)