%I #4 Mar 30 2012 18:56:54
%S 0,0,0,0,0,0,3,15,20,60,140,175,360,720,891,1935,4455,5775,13895,
%T 32487,42484,97188,216580,282165,632706,1418514,1863880,4259520,
%U 9690000,12833436,29366007,66481107,88256147,200571107,452679491
%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n+3)/3.
%K nonn
%O 1,7
%A _Clark Kimberling_