cp's OEIS Frontend

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.

A293607 Number of unlabeled clutters of weight n.

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%I A293607 #7 Oct 20 2017 15:42:43
%S A293607 1,1,1,1,2,2,7,8,23,42
%N A293607 Number of unlabeled clutters of weight n.
%C A293607 A clutter is a connected antichain of finite sets. The weight of a clutter is the sum of cardinalities of its edges.
%e A293607 Non-isomorphic representatives of the a(7) = 8 clutters are:
%e A293607 ((1234567)),
%e A293607 ((12)(13456)), ((123)(1245)), ((123)(1456)),
%e A293607 ((12)(13)(145)), ((12)(13)(234)), ((12)(13)(245)), ((13)(24)(125)).
%Y A293607 Cf. A006126, A007716, A048143, A049311, A283877, A293606.
%K A293607 nonn,more
%O A293607 0,5
%A A293607 _Gus Wiseman_, Oct 13 2017