C(23,10,2) = 8

Method of Construction: simple construction: deleted element from c(v+1,k,t) covering

Lower Bound: Handbook of Combinatorial Designs section on coverings

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