27 ≤ C(23,12,4) ≤ 31
Method of Construction: simple construction: deleted element from c(v+1,k,t) covering
Lower Bound: Schonheim
2 3 4 5 7 9 10 15 17 19 20 23
1 2 7 8 9 10 11 12 16 17 18 20
2 3 4 5 6 9 11 13 16 18 20 23
2 4 6 8 10 11 14 15 18 19 22 23
1 2 3 4 6 7 11 12 14 15 18 20
1 2 4 10 12 13 15 16 18 19 21 23
3 6 8 9 12 13 14 17 18 19 21 23
2 5 9 13 14 15 16 18 19 20 21 22
2 4 5 7 8 13 14 16 17 18 22 23
1 3 4 5 6 9 13 14 15 16 17 21
1 5 6 7 9 10 12 13 15 18 22 23
1 2 3 4 7 12 13 14 15 17 19 22
1 2 3 5 6 7 8 14 16 19 20 23
1 2 4 5 6 7 9 11 12 17 21 23
5 7 8 9 10 11 12 14 15 16 21 23
1 2 3 4 8 9 12 14 20 21 22 23
2 3 5 7 8 10 11 12 13 19 20 21
1 3 6 8 9 11 16 17 19 21 22 23
3 5 7 11 12 13 18 19 20 21 22 23
1 2 5 6 8 9 11 12 13 15 19 20
1 3 8 10 11 13 14 15 17 18 20 23
2 3 6 10 12 15 16 17 20 21 22 23
1 3 4 5 7 9 10 11 14 18 19 21
2 6 7 9 10 11 13 14 17 20 21 22
1 3 4 5 8 9 11 12 15 17 18 22
1 3 4 7 8 11 13 15 16 20 21 22
1 4 5 6 8 10 17 18 19 20 21 22
4 5 9 10 11 12 13 14 16 17 19 20
3 4 6 7 8 9 10 12 13 16 19 22
2 3 6 7 8 11 15 16 17 18 19 21
1 2 3 5 6 10 11 12 14 16 18 22