%I #4 Mar 30 2012 18:56:54
%S 0,0,0,0,1,3,12,30,60,121,217,385,700,1260,2521,4960,9460,20020,38500,
%T 71071,148161,276549,503685,1071525,2006508,3681588,8013256,14981556,
%U 27412041,60042147,111406614,202871284,447617884,828004144
%N Number of nonempty subsets of {1,2,...,n} in which exactly 2/5 of the elements are <= (n+3)/3.
%K nonn
%O 1,6
%A _Clark Kimberling_