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A096546
Values w associated with A096545(n), sorted on z, then on y and finally on x.
5
6, 9, 20, 19, 28, 25, 29, 41, 46, 46, 41, 44, 53, 58, 54, 67, 70, 69, 85, 72, 75, 90, 82, 71, 76, 81, 84, 87, 87, 87, 97, 88, 93, 88, 89, 90, 108, 96, 105, 110, 113, 116, 134, 139, 122, 103, 121, 108, 126, 111, 115, 120, 123, 127, 141, 132, 129, 160, 137, 159, 145, 171
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
Entry 87, for example, is associated with primitive quadruples (x, y, z, w)= (26, 55, 78, 87), (38, 48, 79, 87), (20, 54, 79, 87) satisfying x^3 + y^3 + z^3 = w^3, for 0<x<y<z=A096545(n), with n=28, 29, 30.
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, 4]] (* Jean-François Alcover, Mar 06 2020 *)
CROSSREFS
Primitive quadruples (x, y, z, w) = (A095868, A095867, A096545, A096546).
Sequence in context: A011988 A161782 A154783 * A376472 A357840 A355484
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Jun 25 2004
EXTENSIONS
Extended by Ray Chandler, Jun 28 2004
STATUS
approved