This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A128008 #7 Oct 11 2017 05:08:36 %S A128008 1,5,3,5,11,2,17,13,9,7,33,5,13,21,27,17,29,3,37,25,19,13,33,10,17,41, %T A128008 7,25,29,51,11,15,53,19,99,65,23,27,4,65,57,49,41,33,29,25,21,59,17, %U A128008 43,69,13,53,31,9,41,73,83,37,65,14,33,85,105,43,67,77,29,63,69,89,5 %N A128008 Numerators of rational-valued radii of circles given by 3 distinct integer points in the 3-dimensional Euclidean space. %C A128008 A triangle in the 3-dimensional Euclidean space defines a circumcircle. There exist only certain rational-valued circumradii if the vertices of the triangle have integer coordinates. They are rendered by the pair of sequences A128008/A128009 in increasing order. %Y A128008 See A128009 for denominators. Cf. A128006, A128007, A128010, A128011. %K A128008 frac,nonn %O A128008 1,2 %A A128008 _Heinrich Ludwig_, Feb 14 2007