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 A084872 Number of 5-multiantichains of an n-set. 1
 1, 2, 8, 56, 726, 17938, 722680, 35955180, 1798971434, 83885891894, 3612380896332, 145277787750064, 5534505187364062, 202229611397865690, 7158136006402746464, 247316732670273773108, 8389241054998193347410 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS G. C. Greubel, Table of n, a(n) for n = 0..660 Goran Kilibarda and Vladeta Jovovic, Antichains of Multisets, J. Integer Seqs., Vol. 7, 2004. FORMULA a(n) = (1/5!)*(32^n - 20*24^n + 60*20^n + 20*18^n + 10*17^n - 90*16^n - 120*15^n + 150*14^n + 120*13^n - 480*12^n + 20*11^n + 720*10^n + 120*9^n - 445*8^n + 180*7^n - 1650*6^n + 1650*5^n + 870*4^n - 1740*3^n + 744*2^n). MATHEMATICA Table[(32^n - 20*24^n + 60*20^n + 20*18^n + 10*17^n - 90*16^n - 120*15^n + 150*14^n + 120*13^n - 480*12^n + 20*11^n + 720*10^n + 120*9^n - 445*8^n + 180*7^n - 1650*6^n + 1650*5^n + 870*4^n - 1740*3^n + 744*2^n)/120, {n, 0, 50}] (* G. C. Greubel, Oct 08 2017 *) PROG (PARI) for(n=0, 50, print1((32^n - 20*24^n + 60*20^n + 20*18^n + 10*17^n - 90*16^n - 120*15^n + 150*14^n + 120*13^n - 480*12^n + 20*11^n + 720*10^n + 120*9^n - 445*8^n + 180*7^n - 1650*6^n + 1650*5^n + 870*4^n - 1740*3^n + 744*2^n)/120, ", ")) \\ G. C. Greubel, Oct 08 2017 (MAGMA) [(32^n - 20*24^n + 60*20^n + 20*18^n + 10*17^n - 90*16^n - 120*15^n + 150*14^n + 120*13^n - 480*12^n + 20*11^n + 720*10^n + 120*9^n - 445*8^n + 180*7^n - 1650*6^n + 1650*5^n + 870*4^n - 1740*3^n + 744*2^n)/120: n in [0..50]]; // G. C. Greubel, Oct 08 2017 CROSSREFS Cf. A016269, A047707, A051112-A051118, A084869-A084883. Sequence in context: A203199 A302999 A135079 * A254231 A191713 A191508 Adjacent sequences:  A084869 A084870 A084871 * A084873 A084874 A084875 KEYWORD nonn AUTHOR Goran Kilibarda, Vladeta Jovovic, Jun 10 2003 STATUS approved

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Last modified March 24 01:20 EDT 2019. Contains 321444 sequences. (Running on oeis4.)