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A079189
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Number of anti-commutative closed binary operations (groupoids) on a set of order n.
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5
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1, 1, 8, 5832, 764411904, 32000000000000000, 669462604992000000000000000, 10090701947420325348336258984797490118656, 149274165541848061518941637595308945760198454444667437056, 2832386113499265897149023834314938475799908379160975581551362823935905234944
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = (n^n)*((n^2-n)^((n^2-n)/2)).
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PROG
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(PARI) a(n) = (n^n)*((n^2-n)^((n^2-n)/2)) \\ Andrew Howroyd, Jan 23 2022
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003
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EXTENSIONS
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a(0)=1 prepended, a(8) corrected and a(9) added by Andrew Howroyd, Jan 23 2022
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STATUS
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approved
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