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%I #6 Jul 10 2011 18:42:31
%S 0,0,1,1,4,5,107,0,0,0,5,0,28,488,43389
%N Number of isomorphism classes of non-associative commutative closed binary operations on a set of order n, listed by class size.
%C A079194(n)+A079197(n)+A079200(n)+A079201(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; 0,1; 1,4,5,107; 0,0,0,5,0,28,488,43389
%C A079195(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 A079196(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. A079194, A079198, A079199, A079200, A079201.
%K nonn,tabf
%O 1,5
%A Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003