it's okay to send in more, just look to see if the school has a max. I wouldn't want to send more than that (some cap it off at 5 letter).
I have a list with all the schools and their letter req's so if you want to know a specific school, just ask.
Meanwhile, here is the NYMC:
3+ (2 sci prof, 1 nonscience faculty). Others accepted from individuals who have known candidate in supervisory capacity.
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