%I #4 Mar 30 2012 18:56:54
%S 0,0,0,0,0,10,20,41,77,126,252,392,844,1270,2800,4070,9020,12782,
%T 28679,40022,91286,126048,291018,398125,926177,1256717,2942192,
%U 3965620,9343948,12526280,29689088,39617627,94363367
%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n-4)/2.
%K nonn
%O 1,6
%A _Clark Kimberling_