I trying to find an algorithm that will give me the total number of unique combinations of a sequence of numbers between two people.
If I have the following numbers: 1,3,3,3.
Then this can be split in 2 ways between two people:
Person 1 Person 2
1,3.........3 3
3,3.........1 3
There are 2 combinations here.
Likewise, if I have the following numbers: 1,1,2,2.
Then this can be split in the following ways:
Person 1 Person 2
1,1.........2,2
1,2.........1,2
2,2.........1,1
There are 3 combinations here.
I tried using the following formula
(n+r-1)! / r!(n-1)!
where n is the number of distinct numbers and r is the size of the combinations.
That didn't give me the right answer.
Can anyone help?