Number of ways to choose k from a multiset if order matter

Revision en1, by secomo, 2021-06-26 12:27:40

Example : {1,2,2,3,3}

the answer here is 5 :

{1,2,2} {1,2,3} {1,3,3} {2,2,3} {2,3,3}

I want a formula to calculate this.

I searched through Internet but I did not find a clear answer.

I am not good at math so I want a simple explination If that is possible. Thank you.

Tags #combinatorics

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en2 English secomo 2021-06-26 12:29:33 16
en1 English secomo 2021-06-26 12:27:40 346 Initial revision (published)