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%I #6 May 24 2018 13:23:17
%S 1,0,1,2,10,128
%N Number of unlabeled blobs spanning n vertices without singleton edges.
%C A blob is a connected antichain of finite sets that cannot be capped by a hypertree with more than one branch.
%H Gus Wiseman, <a href="http://www.mathematica-journal.com/2017/12/every-clutter-is-a-tree-of-blobs/">Every Clutter Is a Tree of Blobs</a>, The Mathematica Journal, Vol. 19, 2017.
%e Non-isomorphic representatives of the a(4) = 10 blobs:
%e {{1,2,3,4}}
%e {{1,3,4},{2,3,4}}
%e {{1,3},{1,4},{2,3,4}}
%e {{1,2},{1,3,4},{2,3,4}}
%e {{1,2,4},{1,3,4},{2,3,4}}
%e {{1,2},{1,3},{2,4},{3,4}}
%e {{1,2},{1,3},{1,4},{2,3,4}}
%e {{1,3},{1,4},{2,3},{2,4},{3,4}}
%e {{1,2,3},{1,2,4},{1,3,4},{2,3,4}}
%e {{1,2},{1,3},{1,4},{2,3},{2,4},{3,4}}
%Y Cf. A030019, A035053, A048143, A054921, A134957, A144959, A275307, A286520, A293607, A304118, A304717, A304867.
%K nonn
%O 0,4
%A _Gus Wiseman_, May 24 2018