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%I #7 Jan 05 2020 12:03:15
%S 1,1,1,7,889
%N Number of non-isomorphic fully chiral set-systems covering n vertices.
%C A set-system is a finite set of finite nonempty sets. It is fully chiral if every permutation of the covered vertices gives a different representative.
%e Non-isomorphic representatives of the a(0) = 1 through a(3) = 7 set-systems:
%e 0 {1} {1}{12} {1}{2}{13}
%e {1}{12}{23}
%e {1}{12}{123}
%e {1}{2}{12}{13}
%e {1}{2}{13}{123}
%e {1}{12}{23}{123}
%e {1}{2}{12}{13}{123}
%Y The labeled version is A330229.
%Y First differences of A330294 (the non-covering case).
%Y Unlabeled costrict (or T_0) set-systems are A326946.
%Y BII-numbers of fully chiral set-systems are A330226.
%Y Non-isomorphic fully chiral multiset partitions are A330227.
%Y Fully chiral partitions are A330228.
%Y Fully chiral factorizations are A330235.
%Y MM-numbers of fully chiral multisets of multisets are A330236.
%Y Cf. A000612, A016031, A055621, A083323, A283877, A319637, A330098, A330231, A330232, A330234, A330282.
%K nonn,more
%O 0,4
%A _Gus Wiseman_, Dec 10 2019
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