C(23,13,2) = 5

Method of Construction: lex covering

Lower Bound: Bounds for fixed number of blocks

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