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 A052445 #50 Feb 16 2025 08:32:42 %S A052445 0,0,0,0,1,3,21,345,13429,1109105,162318088,39460518399 %N A052445 Number of simple unlabeled n-node graphs of connectivity 4. %H A052445 Brendan McKay, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2015-July/015022.html">confusion over k-connected graphs</a>, posting to Sequence Fans Mailing List, Jul 08 2015. %H A052445 Jens M. Schmidt, <a href="/A324088/a324088.html">Data files in graph6 format</a> %H A052445 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/k-ConnectedGraph.html">k-Connected Graph</a> %H A052445 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/VertexConnectivity.html">Vertex Connectivity</a> %F A052445 a(n) = A086216(n) - A086217(n). - _Andrey Zabolotskiy_, Nov 20 2017 %e A052445 The a(6) = 3 exactly-4-connected 6-node graphs are the complete graph K_6 with 1, 2, or 3 non-adjacent edges removed. %Y A052445 Cf. A052442, A052443, A052444, A086216, A086217, A259862. %K A052445 nonn,more,hard %O A052445 1,6 %A A052445 _Eric W. Weisstein_ %E A052445 Partially edited by _N. J. A. Sloane_, Jul 08 2015 at the suggestion of _Brendan McKay_ %E A052445 a(8)-a(11) copied from A259862 by _Andrey Zabolotskiy_, Nov 20 2017 %E A052445 a(4)-a(5) corrected by _Andrew Howroyd_, Aug 28 2019 %E A052445 a(12) from _Sean A. Irvine_, Dec 12 2021