A095867 - OEIS

A095867

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

4, 6, 14, 10, 19, 17, 15, 32, 30, 36, 17, 23, 34, 42, 19, 51, 54, 38, 61, 39, 43, 59, 60, 23, 33, 48, 53, 55, 48, 54, 69, 43, 54, 31, 40, 38, 82, 53, 70, 75, 74, 86, 95, 96, 92, 31, 84, 51, 94, 47, 34, 55, 51, 65, 85, 76, 57, 123, 73, 121, 81, 108, 64, 71, 73, 135, 75, 107, 87

(list; graph; refs; listen; history; text; internal format)

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)=4 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, 2]] (* Jean-François Alcover, Mar 06 2020 *)

CROSSREFS

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

Sequence in context: A016072 A335163 A365963 * A253535 A349171 A338658

Adjacent sequences: A095864 A095865 A095866 * A095868 A095869 A095870

KEYWORD

nonn

AUTHOR

Ray Chandler, Jun 28 2004

STATUS

approved