A048085 Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n+3)/3.

0, 0, 0, 0, 2, 3, 12, 30, 40, 86, 182, 245, 560, 1270, 1784, 4070, 9020, 12782, 28679, 63518, 91286, 205478, 455966, 662151, 1485624, 3290520, 4814672, 10782222, 23878212, 35172819, 78678468, 174179258, 257964134, 576312440