A048069 - OEIS

A048069

Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= (n-4)/2.

%I #4 Mar 30 2012 18:56:54

%S 0,0,0,0,0,1,6,12,42,63,168,224,504,630,1270,1527,2937,3465,6930,8184,

%T 18304,21879,54054,65065,165285,198363,491128,584464,1387744,1636284,

%U 3757884,4398954,9980054

%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= (n-4)/2.

%K nonn

%O 1,7

%A _Clark Kimberling_