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%I #12 Feb 15 2015 10:16:02
%S 1,2,57,18544,104208775,12244640803344,36193798266945468968,
%T 3160642595226430678271332032,9374102814860736866561050257041372709,
%U 1067627008939949742128760399369846160513647927040
%N Number of nonisomorphic commutative groupoids with 1 idempotent.
%H <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a>
%K nonn,nice
%O 1,2
%A _Christian G. Bower_, Feb 15 1998 and May 15 1998