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A056052 Number of 7-antichain covers of a labeled n-set. +0
6
490, 1305330, 1076513148, 474700998300, 143480504528862, 33962870686689270, 6808412143396065136, 1214116433267798496480, 198951942958529631990834, 30633642863234275154265690, 4502737302793395778228384164 (list; graph; listen)
OFFSET

5,1

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

K. S. Brown, Dedekind's problem

Eric Weisstein's World of Mathematics, Antichain covers"

FORMULA

a(n)=(1/7!)*(127^n - 42*95^n + 210*79^n + 140*71^n + 210*67^n - 84*65^n + 14*64^n - 819*63^n - 2520*59^n + 2730*55^n + 840*53^n + 840*51^n - 420*50^n + 2940*49^n + 630*47^n - 5040*45^n + 840*44^n - 1260*43^n + 1680*42^n - 9660*41^n + 1260*40^n + 3360*39^n - 7560*38^n + 11130*37^n + 5880*36^n + 9240*35^n + 2982*34^n - 6300*33^n - 8652*32^n - 9905*31^n - 8400*30^n - 8540*29^n + 13860*28^n + 14490*27^n - 5040*26^n + 10500*25^n + 10080*24^n - 8120*23^n - 15050*22^n - 5040*21^n - 11340*20^n + 20580*19^n + 15750*18^n - 1540*17^n - 5810*16^n - 16485*15^n - 21420*14^n + 26250*13^n + 21000*12^n - 29820*11^n + 3500*10^n + 17640*9^n + 2940*8^n - 16016*7^n + 4410*6^n - 9744*5^n + 9744*4^n + 1764*3^n - 3528*2^n + 720).

CROSSREFS

Cf. A051115.

Sequence in context: A118449 A068751 A056936 this_sequence A051115 A060975 A082079

Adjacent sequences: A056049 A056050 A056051 this_sequence A056053 A056054 A056055

KEYWORD

nonn

AUTHOR

Vladeta Jovovic, Goran Kilibarda, Zoran Maksimovic (vladeta(AT)Eunet.yu), Jul 25 2000

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Last modified November 21 14:49 EST 2008. Contains 150807 sequences.


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