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%I #3 Feb 11 2014 17:06:02
%S 1,5,3,5,7,11,2,17,13,9,7,33,19,5,13,21,27,11,14,17,29,3,37,31,25,19,
%T 13,33,10,27,17,41,7,25,18,29,51,11,37,26,15,53,19,99,65,23,27,39,47,
%U 55,91,4,65,57,49,41,33,29,25,67,21,59,17,30,43,69,13,61,35,22,53,31,9
%N Numerators of rational-valued radii of circles given by 3 distinct integer points in the 4-dimensional Euclidean space.
%C A triangle in the 4-dimensional Euclidean space defines a circumcircle. There exist only certain rational-valued circumradii if the vertices of the triangle have integer coordinates. They are listed by the pair of sequences A128010/A128011 in increasing order.
%Y See A128011 for denominators. Cf. A128006, A128007, A128008, A128009.
%K frac,nonn
%O 1,2
%A _Heinrich Ludwig_, Feb 18 2007