C(20,6,2) = 16

Method of Construction: simulated annealing covering

Lower Bound: Schonheim

  1  4  5  6  8 13
  4  5  6  9 11 16
  1  7 10 11 12 16
  2  4  5 12 14 17
  8  9 10 13 15 17
  2  6  9 10 14 18
  4  5  7 14 15 18
  1  2  3 11 15 19
  3 13 14 15 16 19
  3  6  7  9 17 19
  3  8 12 13 18 19
  1  8 11 13 14 20
  1  6  9 12 15 20
  2  7  8 13 16 20
  1 11 16 17 18 20
  3  4  5 10 19 20