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 A353700 #36 Jan 11 2023 11:08:51 %S A353700 1,25,1,625,25,138125,5,4225,625,801125,25,1221025,15625,105625,65, %T A353700 185870425,4225,185870425,625,29641625,29641625,30525625,325,17850625, %U A353700 35409725,1221025,15625,3159797225,105625,763140625,1105,1346691125 %N A353700 Numerator of squared radius of smallest circle passing through exactly n integral points. %C A353700 Schinzel proved such a circle always exists, and the square of the radius of a circle passing through 3 integral points is always rational so the sequence is well-defined. %H A353700 Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a353/A353700.java">Java program</a> (github) %H A353700 S. S. Lacerda, <a href="https://gist.github.com/SofiaSL/eca994e57e519ec16228fa754dd84fd1">schinzel.py</a> %H A353700 E. Pegg, <a href="https://demonstrations.wolfram.com/LatticeCircles/">Lattice Circles</a> %H A353700 Jim Randell, <a href="https://github.com/enigmatic-code/lattice_circles">A collection of minimal radius lattice circles</a> (github) %H A353700 C. Schinzel, <a href="http://doi.org/10.5169/seals-34627">Sur l'existence d'un cercle passant par un nombre donné de points aux coordonnées entières</a>, Enseignement Math, vol. 4, pp. 71-72, 1958. %e A353700 For n=3 a minimal circle is (x - 1/6)^2 + (y - 1/6)^2 = 25/18. %Y A353700 Denominators are A353701. %K A353700 nonn,hard,frac,nice %O A353700 2,2 %A A353700 _Sofia Lacerda_, May 04 2022 %E A353700 Data corrected by _Sean A. Irvine_, Jul 17 2022 %E A353700 a(29)-a(33) from _Jim Randell_, Jan 10 2023