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Revision History for A293606 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Number of unlabeled antichains of weight n.
(history; published version)
#17 by Peter Luschny at Sun Aug 18 04:23:43 EDT 2019
STATUS

reviewed

approved

#16 by Joerg Arndt at Fri Aug 16 11:19:30 EDT 2019
STATUS

proposed

reviewed

#15 by Gus Wiseman at Fri Aug 16 09:26:59 EDT 2019
STATUS

editing

proposed

#14 by Gus Wiseman at Fri Aug 16 09:26:50 EDT 2019
COMMENTS

Also the number of non-isomorphic set multipartitions (multisets of sets) of weight n where every vertex is the unique common element of some subset of the edges. For example, the a(1) = 1 through a(56) = 9 20 set multipartitions are:

STATUS

proposed

editing

#13 by Gus Wiseman at Fri Aug 16 00:52:00 EDT 2019
STATUS

editing

proposed

Discussion
Fri Aug 16
07:30
Joerg Arndt: "a(5) = 9" --> "a(6) = 20" ?
#12 by Gus Wiseman at Thu Aug 15 05:51:23 EDT 2019
COMMENTS

From Gus Wiseman, Aug 15 2019: (Start)

Also the number of non-isomorphic set multipartitions (multisets of sets) of weight n where every vertex is the unique common element of some subset of the edges. For example, the a(1) = 1 through a(5) = 9 set multipartitions are:

{1} {1}{1} {1}{1}{1} {1}{2}{12} {1}{2}{2}{12} {12}{13}{23}

{1}{2} {1}{2}{2} {1}{1}{1}{1} {1}{2}{3}{23} {1}{2}{12}{12}

{1}{2}{3} {1}{1}{2}{2} {1}{1}{1}{1}{1} {1}{2}{13}{23}

{1}{2}{2}{2} {1}{1}{2}{2}{2} {1}{2}{3}{123}

{1}{2}{3}{3} {1}{2}{2}{2}{2} {1}{1}{2}{2}{12}

{1}{2}{3}{4} {1}{2}{2}{3}{3} {1}{1}{2}{3}{23}

{1}{2}{3}{3}{3} {1}{2}{2}{2}{12}

{1}{2}{3}{4}{4} {1}{2}{3}{3}{23}

{1}{2}{3}{4}{5} {1}{2}{3}{4}{34}

{1}{1}{1}{1}{1}{1}

{1}{1}{1}{2}{2}{2}

{1}{1}{2}{2}{2}{2}

{1}{1}{2}{2}{3}{3}

{1}{2}{2}{2}{2}{2}

{1}{2}{2}{3}{3}{3}

{1}{2}{3}{3}{3}{3}

{1}{2}{3}{3}{4}{4}

{1}{2}{3}{4}{4}{4}

{1}{2}{3}{4}{5}{5}

{1}{2}{3}{4}{5}{6}

(End)

STATUS

approved

editing

#11 by N. J. A. Sloane at Fri Oct 20 15:42:29 EDT 2017
STATUS

reviewed

approved

#10 by Andrey Zabolotskiy at Thu Oct 19 04:08:25 EDT 2017
STATUS

proposed

reviewed

#9 by Andrey Zabolotskiy at Fri Oct 13 07:27:45 EDT 2017
STATUS

editing

proposed

#8 by Andrey Zabolotskiy at Fri Oct 13 07:25:53 EDT 2017
STATUS

proposed

editing

Discussion
Fri Oct 13
07:27
Andrey Zabolotskiy: A triangle "T(n,k) = number of antichain covers of an unlabeled k-set of weight n" would be interesting.