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 A192493 #33 Aug 24 2021 21:09:44 %S A192493 1,1,5,25,25,2,5,25,25,13,325,169,65,4,65,17,425,221,9,289,1105,169, %T A192493 85,5,325,85,50,1105,289,25,2125,625,13,325,425,1625,169,1105,125,65, %U A192493 29,2465,4225,1885,725,377,2465,5525,1885,125,8,145,65,841,17,841,845,425,2125,221,6409,9425,9,325,289,145,1105,37,5365,3145,169,2405,925,85,1369,4625,481,625,493,2405,10 %N A192493 Numerators of squared radii of circumcircles of non-degenerate triangles with integer vertex coordinates. %H A192493 Hugo Pfoertner, <a href="/A192493/b192493.txt">Table of n, a(n) for n = 1..9089</a>, covering range R^2 <= 100. %H A192493 Hugo Pfoertner, <a href="/A192493/a192493.pdf">Circles Passing through 3 Points of the Square Lattice</a>, illustrations up to R^2=10. %e A192493 The smallest triangle of lattice points {(0,0),(1,0),(0,1)} has circumradius R=sqrt(2)/2, i.e., R^2=1/2. Therefore a(1)=1, A192494(1)=2. %Y A192493 Cf. A192494 (corresponding denominators), A128006, A128007. %Y A192493 Cf. A346993, A346994, A346995. %K A192493 nonn,frac %O A192493 1,3 %A A192493 _Hugo Pfoertner_, Jul 10 2011