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Number of isomorphism classes of non-anti-commutative closed binary operations (groupoids) on a set of order n.
6

%I #7 Mar 30 2012 17:37:12

%S 1,4,2334,147124304,2216860823492185,13395780829563177947362200,

%T 48974776899548402559651008669035131863,

%U 151979850442580207421627199010701131897617064179661376

%N Number of isomorphism classes of non-anti-commutative closed binary operations (groupoids) on a set of order n.

%C A079187(n)+A079190(n)=A001329(n).

%C Each a(n) is equal to the sum of the elements in row n of A079188.

%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. A079186, A079188, A079190.

%K nonn

%O 1,2

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

%E Edited, corrected and extended by _Christian G. Bower_, Dec 12 2003