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%I #6 Mar 30 2012 17:37:12
%S 1,4,4,24,54,35,356,1044,1488,604,16585,31620,60900,57900,16727,
%T 3461916,1699290,3345420,4744380,3128880,681232,6058301508,265521354,
%U 263429355,439698420,455785470,222132666,38187291
%N Triangle read by rows: T(n,k) = number of labeled semigroups of order n with k idempotents.
%H <a href="/index/Se#semigroups">Index entries for sequences related to semigroups</a>
%e 1; 4,4; 24,54,35; 356,1044,1488,604; ...
%Y Row sums give A023814.
%K nonn,tabl,hard
%O 1,2
%A _Christian G. Bower_, Nov 15 2000