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Number of isomorphism classes of non-anti-associative closed binary operations on a set of order n.
10

%I #6 Jul 10 2011 18:42:30

%S 0,8,3320,178964172

%N Number of isomorphism classes of non-anti-associative closed binary operations on a set of order n.

%C A079177(n)+A079180(n)=A001329(n).

%C Each a(n) is equal to the sum of the elements in row n of A079178.

%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. A079176, A079178, A079180.

%K nonn

%O 1,2

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