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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.

A330345 Number of labeled simple graphs with n vertices whose covered portion has exactly two automorphisms.

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%I A330345 #6 Dec 12 2019 09:33:37
%S A330345 0,0,1,6,42,700,16995
%N A330345 Number of labeled simple graphs with n vertices whose covered portion has exactly two automorphisms.
%e A330345 The a(4) = 42 graphs:
%e A330345   {12}  {12,13}  {12,13,24}  {12,13,14,23}
%e A330345   {13}  {12,14}  {12,13,34}  {12,13,14,24}
%e A330345   {14}  {12,23}  {12,14,23}  {12,13,14,34}
%e A330345   {23}  {12,24}  {12,14,34}  {12,13,23,24}
%e A330345   {24}  {13,14}  {12,23,34}  {12,13,23,34}
%e A330345   {34}  {13,23}  {12,24,34}  {12,14,23,24}
%e A330345         {13,34}  {13,14,23}  {12,14,24,34}
%e A330345         {14,24}  {13,14,24}  {12,23,24,34}
%e A330345         {14,34}  {13,23,24}  {13,14,23,34}
%e A330345         {23,24}  {13,24,34}  {13,14,24,34}
%e A330345         {23,34}  {14,23,24}  {13,23,24,34}
%e A330345         {24,34}  {14,23,34}  {14,23,24,34}
%t A330345 graprms[m_]:=Union[Table[Sort[Sort/@(m/.Rule@@@Table[{p[[i]],i},{i,Length[p]}])],{p,Permutations[Union@@m]}]];
%t A330345 Table[Length[Select[Subsets[Subsets[Range[n],{2}]],Length[graprms[#]]==Length[Union@@#]!/2&]],{n,0,4}]
%Y A330345 The unlabeled version is A330344.
%Y A330345 The covering case is A330297.
%Y A330345 Covering simple graphs are A006129.
%Y A330345 Graphs with exactly two automorphisms are A330297 (labeled covering), A330344 (unlabeled), A330345 (labeled), A330346 (unlabeled covering), A241454 (unlabeled connected).
%Y A330345 Cf. A006125, A143543, A330098, A330228, A330230, A330282, A330343.
%K A330345 nonn,more
%O A330345 0,4
%A A330345 _Gus Wiseman_, Dec 12 2019