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A059081
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Number of 5-element T_0-antichains on a labeled n-set, n=0,..,32.
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2
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0, 0, 0, 0, 6, 2086, 273072, 19371912, 940055760, 35289051840, 1099827892800, 29723466326400, 716351882400000, 15683016533184000, 315722887044364800, 5890186860509952000, 102288867798813696000, 1656523525703574528000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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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.
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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.
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LINKS
| Vladeta Jovovic, Formula for the number of m-element T_0-antichains on a labeled n-set
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FORMULA
| a(n) = (1/5!)*([32]_n - 20*[24]_n + 60*[20]_n + 20*[18]_n + 10*[17]_n - 110*[16]_n - 120*[15]_n + 150*[14]_n + 120*[13]_n - 240*[12]_n + 20*[11]_n + 240*[10]_n + 40*[9]_n - 205*[8]_n + 60*[7]_n - 210*[6]_n + 210*[5]_n + 50*[4]_n - 100*[3]_n + 24*[2]_n), where [k]_n := k*(k - 1)*...*(k - n + 1), [k]_0 = 1.
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CROSSREFS
| Cf. A059079, A059080, A059082, A059083, A059048-A059052.
Sequence in context: A053293 A004817 A089535 * A172943 A182789 A056048
Adjacent sequences: A059078 A059079 A059080 * A059082 A059083 A059084
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KEYWORD
| fini,nonn
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AUTHOR
| Vladeta Jovovic, Goran Kilibarda (vladeta(AT)eunet.rs), Jan 06 2001
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