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A079178
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Number of isomorphism classes of non-anti-associative closed binary operations on a set of order n, listed by class size.
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6
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0, 2, 6, 3, 10, 78, 3229, 2, 1, 12, 30, 246, 495, 48427, 178914959
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OFFSET
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1,2
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COMMENTS
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Elements per row: 1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!)
First four rows: 0; 2,6; 3,10,78,3229; 2,1,12,30,246,495,48427,178914959
A079176(x) is equal to the sum of the products of each element in row x of this sequence and the corresponding element of A079210.
The sum of each row x of this sequence is given by A079177(x).
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LINKS
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003
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STATUS
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approved
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