C(18,7,2) = 10

Method of Construction: simulated annealing covering

Lower Bound: Bounds for fixed number of blocks

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