%I #4 Mar 30 2012 18:56:54
%S 0,0,0,0,0,0,2,3,18,63,84,224,504,630,1270,2420,2937,5742,12012,15015,
%T 35035,84119,108164,260064,601664,767244,1720944,3755844,4738410,
%U 10329750,22591800,28583709,64071194,144780009,184657869
%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= (n+1)/3.
%K nonn
%O 1,7
%A _Clark Kimberling_