C(19,8,2) = 9

Method of Construction: lex covering

Lower Bound: Handbook of Combinatorial Designs section on coverings

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