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 A359571 #13 Sep 01 2023 15:49:40 %S A359571 0,1,6,34,13730 %N A359571 Number of (curved) edges after n iterations of constructing circles from all current vertices using only a compass, starting with one vertex. See the Comments. %C A359571 See A359569 and A359570 for further details and images. %F A359571 For n >= 3, a(n) = A359569(n) + A359570(n) - 1 by Euler's formula. %Y A359571 Cf. A359569 (vertices), A359570 (regions), A359619 (k-gons), A359254, A359047, A358783. %K A359571 nonn,more,hard %O A359571 1,3 %A A359571 _Scott R. Shannon_, Jan 06 2023