Number the people 1 through 60. Make this
10×6 array of the numbers from 1 to 60
Take the first 10 groups as the 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
To get the 2nd set of groups, slide the rows over to
the right like this:
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
Take the ones that extend past the 10th column on the right of
each row, and move them to the front of the rows as below, and
again, the 10 groups of 6 are the columns:
1 2 3 4 5 6 7 8 9 10
20 11 12 13 14 15 16 17 18 19
29 30 21 22 23 24 25 26 27 28
38 39 40 31 32 33 34 35 36 37
47 48 49 50 41 42 43 44 45 46
56 57 58 59 60 51 52 53 54 55
Do that again with the above array; slide them over like this:
1 2 3 4 5 6 7 8 9 10
20 11 12 13 14 15 16 17 18 19
29 30 21 22 23 24 25 26 27 28
38 39 40 31 32 33 34 35 36 37
47 48 49 50 41 42 43 44 45 46
56 57 58 59 60 51 52 53 54 55
Then as before move the ones that extend past the 10th column
on the right to the far left. Then the columns will again
represent the next 10 groups:
1 2 3 4 5 6 7 8 9 10
19 20 11 12 13 14 15 16 17 18
27 28 29 30 21 22 23 24 25 26
35 36 37 38 39 40 31 32 33 34
43 44 45 46 47 48 49 50 41 42
51 52 53 54 55 56 57 58 59 60
Do it once more with the previous array:
1 2 3 4 5 6 7 8 9 10
19 20 11 12 13 14 15 16 17 18
27 28 29 30 21 22 23 24 25 26
35 36 37 38 39 40 31 32 33 34
43 44 45 46 47 48 49 50 41 42
51 52 53 54 55 56 57 58 59 60
And take the columns again as your 10 groups:
1 2 3 4 5 6 7 8 9 10
18 19 20 11 12 13 14 15 16 17
25 26 27 28 29 30 21 22 23 24
32 33 34 35 36 37 38 39 40 31
49 50 51 52 43 44 45 46 47 48
56 57 58 59 60 51 52 53 54 55
Edwin