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 A079207 Number of isomorphism classes of associative non-commutative non-anti-associative non-anti-commutative closed binary operations on a set of order n, listed by class size. 9
 0, 0, 0, 0, 0, 4, 6, 0, 0, 0, 4, 4, 0, 46, 73 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 COMMENTS A079202(n)+A079203(n)+A079204(n)+A079205(n)+A079197(n)+A079207(n)+A079208(n)+A079209(n)+A063524(n)=A079171(n) Elements per row: 1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!) First four rows: 0; 0,0; 0,0,4,6; 0,0,0,4,4,0,46,73 A079240(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 A079241(x). LINKS C. van den Bosch, Closed binary operations on small sets CROSSREFS Cf. A079202, A079203, A079204, A079205, A079197, A079208, A079209, A079240, A079241. Sequence in context: A231407 A005927 A201529 * A259825 A276449 A056945 Adjacent sequences:  A079204 A079205 A079206 * A079208 A079209 A079210 KEYWORD nonn,tabf AUTHOR Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003 STATUS approved

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Last modified May 23 19:07 EDT 2019. Contains 323528 sequences. (Running on oeis4.)