Permutation of identical elements

  • #1
319
0
If we have n object and n1,n2,..nk are identical element. And we take r at a time i.e r < n. Is there a general formulae for the permutation of the above. Or how it is solved? Thanks.
 

Answers and Replies

  • #2
34,987
11,174
Use the binomial coefficients to find the ways to arrange the identical element - one factor per set of identical elements. The last factor is 1 and can be ignored.

As an example, there are (5 choose 3)=(5 choose 2) different permutations of (1,1,1,2,2).
 

Related Threads on Permutation of identical elements

  • Last Post
Replies
2
Views
2K
Replies
1
Views
933
  • Last Post
Replies
2
Views
3K
Replies
18
Views
4K
Replies
2
Views
2K
  • Last Post
Replies
4
Views
901
Replies
5
Views
2K
  • Last Post
Replies
1
Views
685
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
2
Views
2K
Top