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 A362907 #19 May 14 2023 12:37:55 %S A362907 0,0,0,0,1,6,53,501,5889,81786 %N A362907 Number of graphs on n unlabeled nodes with treewidth 3. %H A362907 Wikipedia, <a href="http://en.wikipedia.org/wiki/Treewidth">Treewidth</a>. %e A362907 There is a single graph of treewidth 3 on 4 vertices, which is the complete graph. %o A362907 (SageMath) [sum(1 for g in graphs(n) if g.treewidth() == 3) for n in range(9)] %Y A362907 Column k=3 of A263294. %K A362907 nonn,hard,more %O A362907 0,6 %A A362907 _Martin Rubey_, May 09 2023