In "nchoosek" function, how to do some of elements of matrix are the same?

the title just is question.

I want to get including that

[KSSV]

nchoosek picks the elements if they are same also...

[Brian Kim]

i don't know whats mean. as if A=[6 6 7 7 9 11 13]. same things are 6 and 7.

Answer 1

[Andrei Bobrov]

>> nchoosek(A,2)
ans =
     6     6
     6     7
     6     7
     6     9
     6    11
     6    13
     6     7
     6     7
     6     9
     6    11
     6    13
     7     7
     7     9
     7    11
     7    13
     7     9
     7    11
     7    13
     9    11
     9    13
    11    13
>> nchoosek(unique(A),2)
ans =
     6     7
     6     9
     6    11
     6    13
     7     9
     7    11
     7    13
     9    11
     9    13
    11    13
>>