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 A319190 #37 Mar 12 2020 18:59:53
%S A319190 1,1,3,19,879,5280907,1069418570520767
%N A319190 Number of regular hypergraphs spanning n vertices.
%C A319190 We define a hypergraph to be any finite set of finite nonempty sets. A hypergraph is regular if all vertices have the same degree. The span of a hypergraph is the union of its edges.
%e A319190 The a(3) = 19 regular hypergraphs:
%e A319190 {{1,2,3}}
%e A319190 {{1},{2,3}}
%e A319190 {{2},{1,3}}
%e A319190 {{3},{1,2}}
%e A319190 {{1},{2},{3}}
%e A319190 {{1},{2,3},{1,2,3}}
%e A319190 {{2},{1,3},{1,2,3}}
%e A319190 {{3},{1,2},{1,2,3}}
%e A319190 {{1,2},{1,3},{2,3}}
%e A319190 {{1},{2},{3},{1,2,3}}
%e A319190 {{1},{2},{1,3},{2,3}}
%e A319190 {{1},{3},{1,2},{2,3}}
%e A319190 {{2},{3},{1,2},{1,3}}
%e A319190 {{1,2},{1,3},{2,3},{1,2,3}}
%e A319190 {{1},{2},{1,3},{2,3},{1,2,3}}
%e A319190 {{1},{3},{1,2},{2,3},{1,2,3}}
%e A319190 {{2},{3},{1,2},{1,3},{1,2,3}}
%e A319190 {{1},{2},{3},{1,2},{1,3},{2,3}}
%e A319190 {{1},{2},{3},{1,2},{1,3},{2,3},{1,2,3}}
%t A319190 Table[Sum[SeriesCoefficient[Product[1+Times@@x/@s,{s,Subsets[Range[n],{1,n}]}],Sequence@@Table[{x[i],0,k},{i,n}]],{k,1,2^n}],{n,5}]
%Y A319190 Column sums of A188445.
%Y A319190 Cf. A002829, A005176, A049311, A058891, A110100, A110101, A116539, A283877, A295193, A306017, A319189.
%K A319190 nonn,more
%O A319190 0,3
%A A319190 _Gus Wiseman_, Dec 17 2018
%E A319190 a(6) from _Andrew Howroyd_, Mar 12 2020