SOLUTION: I have 64 people and need to make groups of 8 that will rotate 3 times and not be with the same person more than once. Thank you. Karen

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Question 770659: I have 64 people and need to make groups of 8 that will rotate 3 times and not be with the same person more than once.
Thank you.
Karen

Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
Make an 8x8 grid of numbers 1-64, each number representing
one of the 64 people.

I'll connect the 8 members in each group with lines.

The first 8 groups will consist of the 8 rows:


 1---2---3---4---5---6---7---8

 9--10--11--12--13--14--15--16

17--18--19--20--21--22--23--24 

25--26--27--28--29--30--31--32

33--34--35--36--37--38--39--40 

41--42--43--44--45--46--47--48

49--50--51--52--53--54--55--56

57--58--59--60--61--62--63--64

The second 8 groups will consist of the 8 columns:

 1   2   3   4   5   6   7   8
 |   |   |   |   |   |   |   |
 9  10  11  12  13  14  15  16
 |   |   |   |   |   |   |   |
17  18  19  20  21  22  23  24 
 |   |   |   |   |   |   |   |
25  26  27  28  29  30  31  32
 |   |   |   |   |   |   |   |
33  34  35  36  37  38  39  40 
 |   |   |   |   |   |   |   |
41  42  43  44  45  46  47  48
 |   |   |   |   |   |   |   |
49  50  51  52  53  54  55  56
 |   |   |   |   |   |   |   |
57  58  59  60  61  62  63  64


To make the third 8 groups, make the grid again on the
right as below. Then take the 8 diagonals as the 8 groups.

 1   2   3   4   5   6   7   8   1   2   3   4   5   6   7   8
   \   \   \   \   \   \   \   \ 
 9  10  11  12  13  14  15  16   9  10  11  12  13  14  15  16
      \   \   \   \   \   \   \   \
17  18  19  20  21  22  23  24  17  18  19  20  21  22  23  24 
          \   \   \   \   \   \   \   \
25  26  27  28  29  30  31  32  25  26  27  28  29  30  31  32
              \   \   \   \   \   \   \   \
33  34  35  36  37  38  39  40  33  34  35  36  37  38  39  40 
                  \   \   \   \   \   \   \   \
41  42  43  44  45  46  47  48  41  42  43  44  45  46  47  48
                       \   \   \   \   \   \   \   \
49  50  51  52  53  54  55  56  49  50  51  52  53  54  55  56
                           \   \   \   \   \   \   \   \
57  58  59  60  61  62  63  64  57  58  59  60  61  62  63  64 

Then nobody will be in a group with anybody else more than once.

Edwin