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 A326250 #4 Jun 21 2019 22:45:36
%S A326250 0,0,0,3,50,982,32636,2096723
%N A326250 Number of weakly nesting simple graphs with vertices {1..n}.
%C A326250 Two edges {a,b}, {c,d} are weakly nesting if a <= c < d <= b or c <= a < b <= d.
%H A326250 Gus Wiseman, <a href="/A326250/a326250.png">The a(4) = 50 weakly nesting simple graphs</a>.
%F A326250 Conjecture: A006125(n) = a(n) + A000108(n).
%t A326250 wnsXQ[stn_]:=MatchQ[stn,{___,{x_,y_},___,{z_,t_},___}/;x<=z<t<=y||z<=x<y<=t];
%t A326250 Table[Length[Select[Subsets[Subsets[Range[n],{2}]],wnsXQ]],{n,0,5}]
%Y A326250 Non-nesting set partitions are A000108.
%Y A326250 Non-crossing graphs are A054726.
%Y A326250 Nesting digraphs are A326209.
%Y A326250 Crossing graphs are A326210.
%Y A326250 MM-numbers of nesting multiset partitions are A326256.
%Y A326250 Cf. A000088, A000332, A006125, A117662.
%Y A326250 Cf. A326211, A326243, A326244, A326248, A326257, A326279.
%K A326250 nonn,more
%O A326250 0,4
%A A326250 _Gus Wiseman_, Jun 21 2019