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%I #17 Feb 26 2017 03:11:19
%S 1,1,1,1,2,5,35,643,44606,29199636
%N Number of nonisomorphic partial 1-differential posets up to rank n.
%H P. Byrnes, <a href="http://hdl.handle.net/11299/142992">Structural aspects of differential posets</a>, Ph.D. thesis, University of Minnesota, (2012)
%H Richard P. Stanley, Fabrizio Zanello, <a href="http://arxiv.org/abs/1111.4371">On the rank function of a differential poset</a>, arXiv:1111.4371 [math.CO], 2011-2012.
%e For n<=4, label nodes with the partitions of n for convenience.
%e At n=5, the two possible posets are the Young poset (nodes and covering relations are the partitions of 5) and the poset constructed by covering the partitions (31), (22) and (211) with a common element, then giving each of those partitions another cover, and leaving all other nodes the same.
%K nonn,more
%O 1,5
%A _William J. Keith_, Mar 04 2014
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