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A059048 Triangle A(n,m) of numbers of n-element ordered T_0-antichains on an unlabeled m-set or numbers of T_1-hypergraphs on n labeled nodes with m (not necessary empty) distinct hyperedges (m=0,1,...,2^n). 10
1, 1, 1, 2, 1, 0, 0, 1, 2, 1, 0, 0, 0, 2, 13, 26, 22, 8, 1, 0, 0, 0, 0, 25, 354, 1798, 4822, 8028, 9044, 7240, 4224, 1808, 560, 120, 16, 1, 0, 0, 0, 0, 30, 2086, 45512, 461236, 2797785, 11669660, 36369970, 89356260, 179461250, 302225100, 43458923, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

An antichain on a set is a T_0-antichain if for every two distinct points of the set there exists a member of the antichain containing one but not the other point. T_1-hypergraph is a hypergraph which for every ordered pair (u,v) of distinct nodes has a hyperedge containing u but not v.

REFERENCES

V. Jovovic and G. Kilibarda, On the number of Boolean functions in the Post classes F^{mu}_8, Diskretnaya Matematika, 11 (1999), no. 4, 127-138 (translated in Discrete Mathematics and Applications, 9, (1999), no. 6)

V. Jovovic, G. Kilibarda, On enumeration of the class of all monotone Boolean functions, in preparation.

LINKS

Table of n, a(n) for n=0..51.

V. Jovovic, 3-element unlabeled ordered T_0-antichains"

V. Jovovic, Number A(m,n) of m-element ordered T_0-antichains on an unlabeled n-set

EXAMPLE

[1, 1], [1, 2, 1], [0, 0, 1, 2, 1], [0, 0, 0, 2, 13, 26, 22, 8, 1], .... There are 72 3-element unlabeled ordered T_0-antichains: 2 on 3-set, 13 on 4-set, 26 on 5-set, 22 on 6-set, 8 on 7-set and 1 on 8-set.

CROSSREFS

Cf. A059049-A059052.

Sequence in context: A218380 A152815 A115296 * A257181 A164116 A164118

Adjacent sequences:  A059045 A059046 A059047 * A059049 A059050 A059051

KEYWORD

nonn

AUTHOR

Vladeta Jovovic, Goran Kilibarda, Dec 19 2000

STATUS

approved

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Last modified July 26 01:20 EDT 2021. Contains 346294 sequences. (Running on oeis4.)