A037843 - OEIS

A037843

Number of matrices with n columns whose rows do not cover each other; ordered antichains of subsets of an n-set.

2, 3, 7, 39, 2551, 22928343, 6641112790058484007

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OFFSET

0,1

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..6.

K. S. Brown, Dedekind's problem

Index entries for sequences related to Boolean functions

FORMULA

a(n)=Sum_{k=0..C(n, floor(n/2))}k!*M(n, k) where M(n, k) is the number of distinct monotone Boolean functions of n variables with k mincuts.

CROSSREFS

Cf. A003182, A051112-A051117, A007411, A006602.

Sequence in context: A047024 A182219 A227777 * A355129 A102604 A119662

Adjacent sequences: A037840 A037841 A037842 * A037844 A037845 A037846

KEYWORD

hard,nonn

AUTHOR

Vladeta Jovovic, Goran Kilibarda, Jul 23 2000

STATUS

approved