18 ≤ C(19,13,5) ≤ 21

Method of Construction: dynamic programming covering

Lower Bound: Schonheim

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