Permn not found on my version of matlab, is there an equivalent function?

I am trying to use permn to return a set of permutations with repetition but the function permn returns an undefined function or variable 'permn' error. I am using matlab r2017b. Is there a special library I need or is there a different function that I can use?

[Ashley]

I realized what was going on; new to matlab and didn't realize that file exchange functions were user submitted.

Answer 1

[Walter Roberson]

https://www.mathworks.com/matlabcentral/fileexchange/7147-permn-v--n--k-