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 A223889 #18 Mar 03 2025 20:25:08
%S A223889 0,0,1,7,66,1078,33812,2124864,269617328,68809824944,35197776962400,
%T A223889 36032789666289920,73789365506598519808,302234307608870314427904,
%U A223889 2475886847109430725963593728,40564851077856428731075010538496
%N A223889 The number of connected components of size > 1 over all simple labeled graphs on n nodes.
%F A223889 E.g.f.: (A(x) - x - 1)*B(x) where A(x) is the e.g.f. for A001187 and B(x) is the e.g.f. for A006125.
%t A223889 nn=15;g=Sum[2^Binomial[n,2]x^n/n!,{n,0,nn}];Range[0,nn]!CoefficientList[Series[(Log[g]-x)g,{x,0,nn}],x]
%Y A223889 Cf. A125207.
%K A223889 nonn
%O A223889 0,4
%A A223889 _Geoffrey Critzer_, Mar 28 2013