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 A056048 Number of 5-antichain covers of a labeled n-set. 2
 0, 0, 0, 0, 6, 2116, 291966, 23312156, 1362515742, 65691305652, 2792020643502, 108871903828732, 3995501812110798, 140371634250355508, 4776934559777356158, 158783001150185585628, 5186356918189216064574, 167203226479257200020084, 5337930997910228958536334 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 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 G. C. Greubel, Table of n, a(n) for n = 0..670 K. S. Brown, Dedekind's problem Eric Weisstein's World of Mathematics, Antichain covers FORMULA a(n) = (1/5!) * (31^n - 20*23^n + 60*19^n + 20*17^n + 10*16^n - 110*15^n - 120*14^n + 150*13^n + 120*12^n - 240*11^n + 20*10^n + 240*9^n + 40*8^n - 205*7^n + 60*6^n - 210*5^n + 210*4^n + 50*3^n - 100*2^n + 24). MATHEMATICA Table[(1/5!)*(31^n - 20*23^n + 60*19^n + 20*17^n + 10*16^n - 110*15^n - 120*14^n + 150*13^n + 120*12^n - 240*11^n + 20*10^n + 240*9^n + 40*8^n - 205*7^n + 60*6^n - 210*5^n + 210*4^n + 50*3^n - 100*2^n + 24), {n, 0, 25}] (* G. C. Greubel, Oct 07 2017 *) PROG (PARI) for(n=0, 25, print1((31^n - 20*23^n + 60*19^n + 20*17^n + 10*16^n - 110*15^n - 120*14^n + 150*13^n + 120*12^n - 240*11^n + 20*10^n + 240*9^n + 40*8^n - 205*7^n + 60*6^n - 210*5^n + 210*4^n + 50*3^n - 100*2^n + 24)/120, ", ")) \\ G. C. Greubel, Oct 07 2017 (MAGMA) [(31^n - 20*23^n + 60*19^n + 20*17^n + 10*16^n - 110*15^n - 120*14^n + 150*13^n + 120*12^n - 240*11^n + 20*10^n + 240*9^n + 40*8^n - 205*7^n + 60*6^n - 210*5^n + 210*4^n + 50*3^n - 100*2^n + 24)/120: n in [0..25]]; // G. C. Greubel, Oct 07 2017 CROSSREFS Cf. A051113. Sequence in context: A226461 A172943 A182789 * A051113 A067174 A153300 Adjacent sequences:  A056045 A056046 A056047 * A056049 A056050 A056051 KEYWORD nonn AUTHOR Vladeta Jovovic, Goran Kilibarda, Zoran Maksimovic, Jul 25 2000 STATUS approved

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Last modified September 20 12:05 EDT 2021. Contains 347586 sequences. (Running on oeis4.)