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A293953
Number of linear extensions of a poset whose Hasse diagram consists of n binary shrubs with type S_n joins.
4
1, 5, 169, 19241, 5216485, 2769073949, 2543467934449, 3712914075133121, 8094884285992309261, 25137521105896509819605, 107107542395866078895709049, 607546536582495444795794603801, 4474746926116218974619451907008885, 41907652406924609850893820950967654989
OFFSET
0,2
LINKS
Jeffrey Remmel, S. Zheng, Rises in forests of binary shrubs, arXiv preprint arXiv:1611.09018 [math.CO], 2016-2017.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 29 2017
EXTENSIONS
Terms a(11) and beyond from Lars Blomberg, Oct 31 2017
STATUS
approved