%I #13 Dec 05 2018 04:54:38

%S 1,4,3,1,8,6,2,5,10,1,12,8,4,3,5,7,4,14,17,1,16,10,7,6,4,3,9,16,14,18,

%T 1,20,12,8,5,7,16,18,12,20,11,16,58,3,22,5,9,11,1,24,14,10,6,22,4,8,2,

%U 13,31,11,26,80,3,5,13,1,28,24,16,12,26,22,7,9,4

%N Denominators of rational-valued radii of circles given by 3 distinct integer points in the Euclidean plane.

%C A triangle in the Euclidean plane defines a circumcircle. There exist only certain rational-valued circumradii if the vertices of the triangle have integer coordinates. The circumradii are rendered by the pair of sequences A128006/A128007 in increasing order.

%Y See A128006 for numerators.

%Y Cf. A128008, A128009, A128010, A128011, A192493, A192494.

%K frac,nonn

%O 1,2

%A _Heinrich Ludwig_, Feb 11 2007