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%I #41 May 24 2018 02:36:13
%S 1,1,1,5,84,6348,7743728,2414572893530,56130437190053299918162
%N Number of labeled connected simplicial complexes with n nodes.
%C Also number of connected antichains on a labeled n-set.
%H Patrick De Causmaecker, Stefan De Wannemacker, <a href="http://arxiv.org/abs/1407.4288">On the number of antichains of sets in a finite universe</a>, arXiv:1407.4288 [math.CO], 2014.
%H Greg Huber, <a href="/A048143/a048143.pdf">Letters to N. J. A. Sloane, May 1983</a> [Annotated, corrected, scanned copy]
%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.
%H Gus Wiseman, <a href="/A048143/a048143_4.txt">Sequences enumerating clutters, antichains, hypertrees, and hyperforests, organized by labeling, spanning, and allowance of singletons</a>.
%e For n=3 we could have 2 edges (in 3 ways), 3 edges (1 way), or 3 edges and a triangle (1 way), so a(3)=5.
%e a(5) = 1+75+645+1655+2005+1345+485+115+20+2 = 6348.
%Y Cf. A094033, A094034, A094035, A094036, A094037.
%Y Cf. A000666, A006126, A030019, A054921, A120338, A275307, A285572.
%K nonn,nice,more
%O 0,4
%A _Greg Huber_, May 12 1983
%E More terms from _Vladeta Jovovic_, Jun 17 2006
%E Entry revised by _N. J. A. Sloane_, Jul 27 2006
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