# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a369196 Showing 1-1 of 1 %I A369196 #9 Jan 18 2024 04:40:49 %S A369196 1,2,7,39,320,3584,51405,900947,18661186,445827942,12062839691, %T A369196 364451604095,12157649050827,443713171974080,17583351295466338, %U A369196 751745326170662049,34485624653535808340,1689485711682987916502,88030098291829749593643,4860631073631586486397141 %N A369196 Number of labeled loop-graphs with n vertices and at most as many edges as covered vertices. %F A369196 Binomial transform of A369194. %e A369196 The a(0) = 1 through a(2) = 7 loop-graphs: %e A369196 {} {} {} %e A369196 {{1}} {{1}} %e A369196 {{2}} %e A369196 {{1,2}} %e A369196 {{1},{2}} %e A369196 {{1},{1,2}} %e A369196 {{2},{1,2}} %t A369196 Table[Length[Select[Subsets[Subsets[Range[n],{1,2}]],Length[#]<=Length[Union@@#]&]],{n,0,5}] %Y A369196 The version counting all vertices is A066383, without loops A369192. %Y A369196 The loopless case is A369193, with case of equality A367862. %Y A369196 The covering case is A369194, connected A369197, minimal case A001862. %Y A369196 The case of equality is A369198, covering case A368597. %Y A369196 A000085, A100861, A111924 count set partitions into singletons or pairs. %Y A369196 A006125 counts simple graphs, also loop-graphs if shifted left. %Y A369196 A006129 counts covering graphs, unlabeled A002494. %Y A369196 A054548 counts graphs covering n vertices with k edges, with loops A369199. %Y A369196 A322661 counts covering loop-graphs, unlabeled A322700. %Y A369196 A368927 counts choosable loop-graphs, covering A369140. %Y A369196 A369141 counts non-choosable loop-graphs, covering A369142. %Y A369196 Cf. A000169, A000272, A000666, A001187, A006649, A057500, A062740, A116508, A367863, A369145. %K A369196 nonn %O A369196 0,2 %A A369196 _Gus Wiseman_, Jan 17 2024 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE