login
Primitive Pythagorean Quadruples a^2+b^2+c^2=d^2, 0<a<=b<=c<=d, gcd(a,b,c,d)=1, sorted by d, then c, then b; sequence gives long even leg values.
2

%I #3 Mar 30 2012 17:29:19

%S 2,6,4,8,6,6,12,10,14,12,12,10,6,18,16,16,8,20,18,18,22,16,20,22,10,

%T 14,10,26,16,24,24,18,22,14,30,20,20,28,28,8,32,32,26,30,30,10,24,28,

%U 28,36,26,22,26,34,34,14,24,24,32,24,12,30,30,38,18,42,42,28,28,20,40,40

%N Primitive Pythagorean Quadruples a^2+b^2+c^2=d^2, 0<a<=b<=c<=d, gcd(a,b,c,d)=1, sorted by d, then c, then b; sequence gives long even leg values.

%C One of a,b,c is odd, other two are even for primitive Pythagorean quadruples.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PythagoreanQuadruple.html">Pythagorean Quadruple.</a>

%Y Cf. A096907, A096908, A096909.

%K nonn

%O 1,1

%A _Ray Chandler_, Aug 15 2004