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 A079205 Number of isomorphism classes of non-associative non-commutative anti-associative anti-commutative closed binary operations on a set of order n, listed by class size. 9

%I

%S 0,2,0,0,2,0,0,0,0,2,0,29,0,237,4374

%N Number of isomorphism classes of non-associative non-commutative anti-associative anti-commutative closed binary operations on a set of order n, listed by class size.

%C A079202(n)+A079203(n)+A079204(n)+A079205(n)+A079197(n)+A079207(n)+A079208(n)+A079209(n)+A063524(n)=A079171(n)

%C Elements per row: 1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!)

%C First four rows: 0; 2,0; 0,2,0,0; 0,0,2,0,29,0,237,4374

%C A079236(x) is equal to the sum of the products of each element in row x of this sequence and the corresponding element of A079210.

%C The sum of each row x of this sequence is given by A079237(x).

%H C. van den Bosch, <a href="http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a>

%H <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a>

%Y Cf. A079202, A079203, A079204, A079197, A079207, A079208, A079209, A079236, A079237.

%K nonn,tabf

%O 1,2

%A Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003

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Last modified May 19 16:36 EDT 2019. Contains 323395 sequences. (Running on oeis4.)