C(55,25,2) = 7

Created by: LJCR

Method of Construction: Multiple of (11,5,2) covering

Lower Bound: Schonheim

  1  2  4  5 11 12 13 15 16 22 23 24 26 27 33 34 35 37 38 44 45 46 48 49 55
  1  3  4  8 11 12 14 15 19 22 23 25 26 30 33 34 36 37 41 44 45 47 48 52 55
  1  6  7  9 10 12 17 18 20 21 23 28 29 31 32 34 39 40 42 43 45 50 51 53 54
  2  3  7  8  9 13 14 18 19 20 24 25 29 30 31 35 36 40 41 42 46 47 51 52 53
  2  4  6 10 11 13 15 17 21 22 24 26 28 32 33 35 37 39 43 44 46 48 50 54 55
  3  5  6  8 10 14 16 17 19 21 25 27 28 30 32 36 38 39 41 43 47 49 50 52 54
  4  5  7  9 11 15 16 18 20 22 26 27 29 31 33 37 38 40 42 44 48 49 51 53 55