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 A385162 #11 Jul 24 2025 09:31:19 %S A385162 4,184,8956,79272,455664,1420624,4576632 %N A385162 Place a point on the integer coordinates, up to |n|, along all four axial directions on a Cartesian plane, and then join a circle through every unordered triple of non-collinear points: a(n) is the number of distinct (curved) edges formed from the intersections of the circles. %H A385162 Scott R. Shannon, <a href="/A385162/a385162.jpg">Image for n = 2</a>. The 4 x 2 = 8 starting points are shown as white dots. %F A385162 a(n) = A385160(n) + A385161(n) - 1 by Euler's formula. %Y A385162 Cf. A385159 (total circles), A385160 (vertices), A385161 (regions), A384703, A374827, A373108, A359571. %K A385162 nonn,more %O A385162 1,1 %A A385162 _Scott R. Shannon_, Jul 10 2025