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%I #4 Mar 30 2012 18:56:54
%S 0,0,0,0,0,5,15,35,70,141,261,405,765,1485,2310,4954,10634,16575,
%T 35945,75725,113815,240385,502945,744345,1595433,3411849,5036862,
%U 10959446,23631286,34636245,75326163,162418479,236331302,514828047
%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n-3)/3.
%K nonn
%O 1,6
%A _Clark Kimberling_