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%I #6 Jul 10 2011 18:42:30
%S 0,2,3,1,12,71,3222,0,1,14,23,270,495,48748,178932213
%N Number of isomorphism classes of non-associative closed binary operations on a set of order n, listed by class size.
%C A079174(n)+A079175(n)=A079171(n)
%C Elements per row: 1,2,4,8,16,30,60,96 (A027423, number of positive divisors of n!)
%C First four rows: 0; 2,3; 1,12,71,3222; 0,1,14,23,270,495,48748,178932213
%C The sum of each row n is given by A079173(n).
%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. A079172, A079173, A079175.
%K nonn,tabf
%O 1,2
%A Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003
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