R - find all possible combinations of numbers WITH constraints on combination length

Question

Let's say you have the following vector of numbers:

1, 2, 3, 4, 5

I want to find all possible combinations of numbers with the combination length 3. The combinations must not overlap, ie 1, 2, 3 is the same as 1, 3, 2 and only one of those should appear in the output!

So, the answers would be:

1, 2, 3
1, 2, 4
1, 2, 5
1, 3, 4
1, 3, 5
1, 4, 5
2, 3, 4
2, 3, 5
2, 4, 5
3, 4, 5

This is just a simple example, in reality I have a vector of length 10000 and I need to find all combinations with length 8000. What code would you use to generate those combinations in R?

Answer 1

@chinsoon12 suggested the package RcppAlgos . I investigated it and found that the following works:

comboIter(1:10000, 8000)