All combinations of specific numbers with specific length in R

Question

I have the numbers 1, 2, 3, 4.

I want to create all the vectors of length 14, such that the number 1 appears 4 times, 2 appears 3 times, 3 appears 5 times and 4 appears 2 times, that is:

4 times + 3 times + 5 times + 2 times = length 14.

For example, three of these vectors are:

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

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

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

and so on.

I have tried to use combn but it was not successful.

The number of these vector is equal to choose(14,4)*choose(14-4,3)*choose(14-4-3,5)*choose(14-4-3-5,2).

EDIT

Using permn(c(1,1,1,1,2,2,2,3,3,3,3,3,4,4)), I will create, for example the vector 1,1,1,1,2,2,2,3,3,3,3,3,4,4 many times, that is I will have duplicated vectors. Then I have to use unique. But it is not worth creating duplicated vectors and then to keep the unique ones, since I want only the unique ones, that is the vector 1,1,1,1,2,2,2,3,3,3,3,3,4,4 just one time.

So, the answer in question Generating all distinct permutations of a list in R creates duplicated vectors.

*"create all the vectors"* Unless I misunderstood, that'll be *a lot* (!) of combinations. Do you really want to create *all* combinations? — Maurits Evers, Sep 19 '19 at 09:38
https://stackoverflow.com/questions/11095992/generating-all-distinct-permutations-of-a-list-in-r — user2974951, Sep 19 '19 at 09:41
With `library(combinat)`you can use e.g. `unique(permn(c(1,1,2,2,3,3)))`. But with the length of you vectors you exceed the memory limit... — Chelmy88, Sep 19 '19 at 09:49
@Chelmy88 I think that I do not have to do this, because of the memory limit as you correctly stated. — Vassilis Chasiotis, Sep 19 '19 at 09:58
@VassilisChasiotis Let's call your vector `x <- c(1,1,1,1,2,2,2,3,3,3,3,3,4,4)`; you do realise that there are `factorial(length(x))/prod(factorial(table(x)))` or `2522520` combinations? Just in terms of memory, that would be quite significant (around 0.5 Gb if I'm not mistaken). — Maurits Evers, Sep 19 '19 at 10:03
@MauritsEvers Of course, I know it. But I have to create them. — Vassilis Chasiotis, Sep 19 '19 at 10:04
@VassilisChasiotis Take a look at the dupe target link, which should address your question. If your issue is in fact a different one, please let me know and I'll re-open. — Maurits Evers, Sep 19 '19 at 10:09
@MauritsEvers my question is duplicated. The answer is in https://stackoverflow.com/questions/5671149/permute-all-unique-enumerations-of-a-vector-in-r. — Vassilis Chasiotis, Sep 19 '19 at 10:23
@MauritsEvers, I would argue that the more canonical dupe target is https://stackoverflow.com/q/22569176/4408538 — Joseph Wood, Sep 19 '19 at 11:39

All combinations of specific numbers with specific length in R

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