A096907 Primitive Pythagorean Quadruples a^2+b^2+c^2=d^2, 0

1, 2, 4, 1, 6, 2, 3, 2, 2, 8, 1, 6, 6, 1, 8, 4, 4, 4, 6, 3, 3, 12, 9, 7, 10, 2, 2, 2, 12, 11, 3, 14, 6, 6, 5, 17, 8, 7, 4, 8, 4, 1, 15, 6, 1, 6, 8, 12, 3, 3, 19, 14, 2, 13, 2, 10, 23, 12, 9, 4, 4, 18, 7, 9, 2, 6, 2, 20, 4, 16, 13, 8, 5, 18, 18, 6, 11, 2, 6, 23, 12, 9, 4, 15, 12, 4, 22, 14, 1, 14

Offset: 1

Author

Ray Chandler, Aug 15 2004

Keywords

• nonn
• look

Links

• Ivan Neretin, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Pythagorean Quadruple.

Crossrefs

Cf. A096908, A096909, A096910.

Programs

Mathematica

mx = 50; res = {}; Do[If[GCD[b, c, d] > 1, Continue[]]; If[IntegerQ[a = Sqrt[d^2 - b^2 - c^2]] && a > 0 && a <= b, AppendTo[res, {a, b, c, d}]], {d, mx}, {c, d}, {b, c}]; res[[All, 1]] (* Ivan Neretin, May 24 2015 *)