How to generate the equal number of groups per week that have members that change the group every week - excel

Question

I have been trying to create an excel that I can use to assign members to a group per week. I need to make sure that each member is in the different group every week.
Below is my excel and here is the formula I use in B3
=INDEX(UNIQUE(RANDARRAY(2, 10, 1, 11)), SEQUENCE(1), {1,2,3,4,5,6,7,8,9,10,11})
The issue i cannot fix is the fact that the groups differ in sizes? Any ideas please.
Week 1 2
PPLs
1 7 8
2 6 11
3 1 3
4 2 7
5 9 7
6 2 10
7 4 8
8 4 5
9 10 8
10 8 9
11 3 6
12 8 6
13 7 9
14 7 8
15 5 8
16 5 8
17 8 8
18 8 10
19 4 9
20 3 2
21 10 9
22 2 10
23 10 6
24 9 3
25 4 9
26 7 6
27 10 7
28 7 7
29 10 5
30 2 5
31 6 6
32 8 8
33 4 4
34 9 10
35 5 9
36 9 7
37 5 7
38 10 9
39 2 10
40 6 5
41 9 2

Answer 1

2 thoughts : simple&(somewhat)repeatable OR noExcel&random.
[ simple&(somewhat)repeatable ]
2 sets only.
Set 1 : group 1 is {member 1-10}, group 2 is {member 11-20} .. group 10 is {member 91-100}
Set 2 : group 1 is {member 1,11,21,31,41,51,61,71,81,91}, group 2 is {member 2,12,22,32,42,52,62,72,82,92} .. group 10 is {member 10,20,30,40,50,60,70,80,90,100}
p/s : although member 1 is always is group 1.. I'd consider it is as a valid group change, since ALL other members of group 1 had changed.
[ noExcel&random ]
Ever heard of 10x10 sudoku? it is widely available online. I have no specific one.. But Sudoku, IS what I meant by noExcel.
example 10x10 sudoku solution :
how to use it :
get 5 different (different is important) solved 10x10 sudoku set, and put it one on top of each other. We should get a 10(col)x50(row) table.
Sort by all 1st row, shall have the sequence (from top, in column 1) : 1,1,1,1,1,2,2,2,2,2,3,3,3,3,3, .. 9,9,9,9,9,10,10,10,10,10
Since we have 50 members (10groups, 5members each). Column 1 will be the assigned group for 50 respective (row) member in week1, Column 2 will be the assigned group for week2... and so on.
if every week is different group, then by week 11 it will come back to his/her original group. OR .. another (5 10x10 sudoku) set perhaps?
(If the idea is unclear.. please ask)
AFAIK. with the rules of sudoku itself, each member(row) will have a different group each week(column), and each element (group number) WILL be repeated for 5 times for each week(column). Thus, solve the
the fact that the groups differ in sizes
part. (please share if this doesn't work though..)
ref : I used https://sudokuspoiler.azurewebsites.net/Sudoku/Sudoku10 to solve http://www.sudoku4me.com/sudoku%2010x10.php puzzle (this solver need 0 to be replaced with 10). As long as it is a valid sudoku solution, it should be fine. Some sudoku use letters instead of numbers. Still, the idea applies.
p/s : I tried excel built in random number generator to generate a ranked (sorted) list, but still end up unable get consistent 5 members per group arrangement, with different group each week (same trouble as OP). I had a fond memory with 9x9 Sudoku, glad to know it came in handy for this solution.