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 A079189 Number of anti-commutative closed binary operations (groupoids) on a set of order n. 4
 1, 8, 5832, 764411904, 32000000000000000, 669462604992000000000000000, 10090701947420325348336258984797490118656, 181258495964203522486308107281962138904949048737792 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A079176(n)+A079179(n)=A002489(n). Each a(n) is equal to the sum of the products of each element in row n of A079191 and the corresponding element of A079210. LINKS C. van den Bosch, Closed binary operations on small sets FORMULA (n^n)((n^2-n)^((n^2-n)/2)) CROSSREFS Cf. A079186, A079190, A079191. a(n)=A023813(n)*A023813(n-1). Sequence in context: A316952 A317732 A179151 * A278384 A114133 A221233 Adjacent sequences:  A079186 A079187 A079188 * A079190 A079191 A079192 KEYWORD nonn AUTHOR Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003 EXTENSIONS Edited and extended by Christian G. Bower, Dec 12 2003 STATUS approved

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Last modified October 21 11:42 EDT 2019. Contains 328296 sequences. (Running on oeis4.)