A369193 Number of labeled simple graphs with n vertices and at most as many edges as covered (non-isolated) vertices.
1, 1, 2, 8, 57, 608, 8614, 151365, 3162353, 76359554, 2088663444, 63760182536, 2147325661180, 79051734050283, 3157246719905273, 135938652662043977, 6275929675565965599, 309242148569525451140, 16197470691388774460758, 898619766673014862321176, 52639402023471657682257626
Offset: 0
Keywords
Examples
The a(0) = 1 through a(3) = 8 graphs: {} {} {} {} {{1,2}} {{1,2}} {{1,3}} {{2,3}} {{1,2},{1,3}} {{1,2},{2,3}} {{1,3},{2,3}} {{1,2},{1,3},{2,3}}
Crossrefs
The version counting all vertices is A369192.
Programs
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Mathematica
Table[Length[Select[Subsets[Subsets[Range[n],{2}]], Length[#]<=Length[Union@@#]&]],{n,0,5}]
Formula
Binomial transform of A369191.