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%I #5 Mar 30 2012 18:56:53
%S 0,0,0,0,0,2,3,15,20,60,75,175,210,435,511,1071,1260,2940,3510,8910,
%T 10725,27345,32835,80795,96382,230230,273273,649805,770315,1860131,
%U 2208115,5426995,6451500,15974220
%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n-1)/2.
%K nonn
%O 1,6
%A _Clark Kimberling_