C(26,15,2) = 5

Method of Construction: lexicographic greedy covering

Lower Bound: Bounds for fixed number of blocks

  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15
  1  2  3  4 16 17 18 19 20 21 22 23 24 25 26
  5  6  7  8  9 10 11 12 16 17 18 19 20 21 22
  5  6  7  8  9 10 11 12 13 14 15 23 24 25 26
  1  2  3  4  5 13 14 15 16 17 18 19 20 21 22