C(25,9,2) = 11

Method of Construction: lex covering

Lower Bound: Schonheim

  1  2  3  4  5  6  7  8  9
  1 10 11 12 13 14 15 16 17
  1 18 19 20 21 22 23 24 25
  2  3  4 10 11 12 18 19 20
  2  3  4 13 14 15 21 22 23
  5  6  7 10 11 12 21 22 23
  5  6  7 13 14 15 18 19 20
  2  3  4  5  6 16 17 24 25
  8  9 10 11 12 13 14 24 25
  8  9 16 17 18 19 20 21 22
  7  8  9 15 16 17 23 24 25