19 ≤ C(19,11,4) ≤ 23

Method of Construction: dynamic programming covering

Lower Bound: Schonheim

  1  2  3  4  5  6  7  8  9 11 12
  1  2  3  4  5  6  7  8  9 13 14
  1  2  3  4  5  6  7  8  9 10 15
  5  6  7  8  9 10 11 12 13 14 15
  2  3  4  8  9 10 11 12 13 14 15
  2  3  4  6  7 10 11 12 13 14 15
  1  6  7  8  9 10 11 12 13 14 15
  1  2  3  4  5 10 11 12 13 14 15
  1  2  3  5  6  9 11 16 17 18 19
  2  3  4  6  7 10 12 16 17 18 19
  3  4  5  7  8 11 13 16 17 18 19
  4  5  6  8  9 12 14 16 17 18 19
  5  6  7  9 10 13 15 16 17 18 19
  1  6  7  8 10 11 14 16 17 18 19
  2  7  8  9 11 12 15 16 17 18 19
  1  3  8  9 10 12 13 16 17 18 19
  2  4  9 10 11 13 14 16 17 18 19
  3  5 10 11 12 14 15 16 17 18 19
  1  4  6 11 12 13 15 16 17 18 19
  1  2  5  7 12 13 14 16 17 18 19
  2  3  6  8 13 14 15 16 17 18 19
  1  3  4  7  9 14 15 16 17 18 19
  1  2  4  5  8 10 15 16 17 18 19