30 ≤ C(15,6,3) ≤ 31
Method of Construction: simulated annealing covering
Lower Bound: Schonheim
3 4 5 6 7 8
1 2 5 6 9 10
2 7 8 9 11 12
1 3 4 10 11 12
2 4 5 6 9 13
1 3 5 8 10 13
1 2 4 7 11 13
6 8 9 10 11 13
1 5 7 8 12 13
3 6 7 9 12 13
2 4 8 10 12 13
1 2 3 9 10 14
2 3 6 7 11 14
1 4 8 9 11 14
4 7 9 10 11 14
2 3 5 8 12 14
1 5 7 9 12 14
4 5 6 10 12 14
2 3 4 5 9 15
1 3 6 7 10 15
1 4 5 6 11 15
3 5 8 9 11 15
2 5 7 10 11 15
1 2 6 8 12 15
4 7 9 10 12 15
3 6 11 12 13 15
4 6 7 8 14 15
2 3 4 13 14 15
1 6 9 13 14 15
7 8 10 13 14 15
5 11 12 13 14 15