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 A059079 Number of n-element T_0-antichains on a labeled set. 5
 2, 5, 19, 16654, 2369110564675, 5960531437586238714806902334250676, 479047836152505670895481840783987408043359908583921478726185296900312296071642855730299 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 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. 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. Vladeta Jovovic, Illustration EXAMPLE a(0) = (1/0!)*[1!*e] = 2; a(1) = (1/1!)*[2!*e] = 5; a(2) = (1/2!)*([4!*e] - 2*[3!*e] + [2!*e]) = 19; a(3) = (1/3!)*([8!*e] - 6*[6!*e] + 6*[5!*e] + 3*[4!*e] - 6*[3!*e] + 2*[2!*e]) = 16654, where [n!*e]=floor(n!*exp(1)). CROSSREFS Cf. A059080-A059083, A059048-A059052, A000522. Sequence in context: A187602 A260140 A270556 * A177494 A136900 A136898 Adjacent sequences: A059076 A059077 A059078 * A059080 A059081 A059082 KEYWORD hard,nonn AUTHOR Vladeta Jovovic, Goran Kilibarda, Dec 23 2000 STATUS approved

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Last modified December 8 23:37 EST 2023. Contains 367681 sequences. (Running on oeis4.)