Functions are an essential part of programming languages and make the code clearer. Why wouldn't you want to use them in matlab?
Recursion also works in matlab, and in this case, I don't see any problem with using recursion. So once again, why would you not want to use it?
I would just simply use the exact same code structure. It's trivial to rewrite in matlab (just replacing printf by fprintf and [] by () is pretty much all that is required). However, I would add comments to the code and use meaningful variable names, so that whoever reads the code doesn't have to remember what the heck x, i and p are supposed to represent.
