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 A358887 #14 Dec 06 2022 19:33:37 %S A358887 5,37,705,4549,42357,94525,531485,1250681,3440621,5985201 %N A358887 Number of vertices formed inside a square with edge length 1 by the straight line segments mutually connecting all vertices and points that divide the sides into segments with lengths equal to the Farey series of order n = A006842(n,k)/A006843(n,k), k = 1..A005728(n). %C A358887 The number of points along each edge is given by A005728(n). %H A358887 Scott R. Shannon, <a href="/A358887/a358887.png">Image for n = 1</a>. %H A358887 Scott R. Shannon, <a href="/A358887/a358887_1.png">Image for n = 2</a>. %H A358887 Scott R. Shannon, <a href="/A358887/a358887_2.png">Image for n = 3</a>. %H A358887 Scott R. Shannon, <a href="/A358887/a358887_3.png">Image for n = 4</a>. %H A358887 Wikipedia, <a href="https://en.wikipedia.org/wiki/Farey_sequence">Farey sequence</a>. %F A358887 a(n) = A358888(n) - A358886(n) + 1 by Euler's formula. %Y A358887 Cf. A358888 (edges), A358886 (regions), A358889 (k-gons), A006842, A006843, A005728, A358882, A358883. %Y A358887 The Farey Diagrams Farey(m,n) are studied in A358298-A358307 and A358882-A358885, the Completed Farey Diagrams of order (m,n) in A358886-A358889. %K A358887 nonn,more %O A358887 1,1 %A A358887 _Scott R. Shannon_ and _N. J. A. Sloane_, Dec 05 2022