A095868 Values x associated with A096545(n), sorted on z, then on y and finally on x.

3, 1, 7, 3, 18, 4, 11, 6, 27, 3, 2, 16, 29, 15, 12, 22, 7, 36, 50, 34, 38, 58, 19, 14, 31, 25, 28, 26, 38, 20, 45, 21, 32, 25, 17, 25, 15, 19, 33, 29, 50, 23, 86, 94, 19, 12, 49, 13, 23, 16, 3, 9, 44, 13, 72, 5, 38, 69, 44, 3, 12, 107, 31, 1, 71, 1, 22, 96, 65, 48, 69, 48, 46, 59

Offset

1,1

Comments

For 0<x<y<z, the primitive quadruples (x,y,z,w) satisfy x^3 + y^3 + z^3 = w^3.

Links

David A. Corneth, Table of n, a(n) for n = 1..13798 (terms corresponding to z <= 8000)

Fred Richman, Sums of Three Cubes

Example

a(1)=3 corresponding to the quadruple (3,4,5,6).

Mathematica

s[w_] := Solve[0 < x < y < z && x^3 + y^3 + z^3 == w^3 && GCD[x, y, z, w] == 1, {x, y, z}, Integers];
xyzw = Reap[For[w = 1, w <= 200, w++, sw = s[w]; If[sw != {}, Print[{x, y, z, w} /. sw; Sow[{x, y, z, w} /. sw ]]]]][[2, 1]] // Flatten[#, 1]&;
SortBy[xyzw, {#[[3]]&, #[[2]]&, #[[1]]&}][[All, 1]] (* Jean-François Alcover, Mar 06 2020 *)

Crossrefs

Primitive quadruples (x, y, z, w) = (A095868, A095867, A096545, A096546).

Sequence in context: A342268 A316742 A189050 * A140962 A013602 A328464

Adjacent sequences: A095865 A095866 A095867 * A095869 A095870 A095871

Keyword

nonn

Author

Ray Chandler, Jun 28 2004

Status

approved