login
A330343
Number of labeled fully chiral simple graphs (also called identity or asymmetric graphs) covering n vertices.
3
1, 0, 0, 0, 0, 5760, 766080, 149022720, 48990251520, 28928242022400, 32147584690636800, 69035206021583155200
OFFSET
1,6
COMMENTS
In a fully chiral graph, every permutation of the vertices gives a different representative, so the only automorphism is the identity.
FORMULA
a(n) = n! * A003400(n).
MATHEMATICA
graprms[m_]:=Union[Table[Sort[Sort/@(m/.Rule@@@Table[{p[[i]], i}, {i, Length[p]}])], {p, Permutations[Union@@m]}]];
Table[Length[Select[Subsets[Subsets[Range[n], {2}]], Length[graprms[#]]==n!&]], {n, 5}] (* brute force, not for computation *)
CROSSREFS
The unlabeled version is A003400.
Identity trees are A004111.
Covering simple graphs are A006129.
Full chiral integer partitions are A330228.
Fully chiral factorizations are A330235.
Fully chiral set-systems are A330229 (labeled covering), A330282 (labeled), A330294 (unlabeled), A330295 (unlabeled covering).
Graphs with exactly two automorphisms are A330297 (labeled covering), A330344 (unlabeled), A330345 (labeled), A330346 (unlabeled covering), A241454 (unlabeled connected).
Sequence in context: A251872 A190466 A157988 * A055354 A053862 A235393
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, Dec 12 2019
STATUS
approved