

A059048


Triangle A(n,m) of numbers of nelement ordered T_0antichains on an unlabeled mset or numbers of T_1hypergraphs 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
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OFFSET

0,4


COMMENTS

An antichain on a set is a T_0antichain if for every two distinct points of the set there exists a member of the antichain containing one but not the other point. T_1hypergraph 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, 127138 (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, 3element unlabeled ordered T_0antichains"
V. Jovovic, Number A(m,n) of melement ordered T_0antichains on an unlabeled nset


EXAMPLE

[1, 1], [1, 2, 1], [0, 0, 1, 2, 1], [0, 0, 0, 2, 13, 26, 22, 8, 1], .... There are 72 3element unlabeled ordered T_0antichains: 2 on 3set, 13 on 4set, 26 on 5set, 22 on 6set, 8 on 7set and 1 on 8set.


CROSSREFS

Cf. A059049A059052.
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



