A048095 Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= sqrt(n).

0, 0, 0, 2, 3, 4, 5, 6, 18, 21, 24, 27, 30, 33, 36, 138, 156, 175, 195, 216, 238, 261, 285, 310, 1150, 1260, 1375, 1495, 1620, 1750, 1885, 2025, 2170, 2320, 2475, 11035, 11935, 12880, 13871, 14909, 15995, 17130, 18315, 19551, 20839