A369191 Number of labeled simple graphs covering n vertices with at most n edges.
1, 0, 1, 4, 34, 387, 5686, 102084, 2162168, 52693975, 1450876804, 44509105965, 1504709144203, 55563209785167, 2224667253972242, 95984473918245388, 4439157388017620554, 219067678811211857307, 11489425098298623161164, 638159082104453330569185
Offset: 0
Keywords
Examples
The a(0) = 1 through a(3) = 4 graphs: {} . {{1,2}} {{1,2},{1,3}} {{1,2},{2,3}} {{1,3},{2,3}} {{1,2},{1,3},{2,3}}
Crossrefs
Programs
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Mathematica
Table[Length[Select[Subsets[Subsets[Range[n], {2}]],Length[Union@@#]==n&&Length[#]<=n&]],{n,0,5}]
Formula
Inverse binomial transform of A369193.
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