I think our messages all crossed in at the same time, but we all agree about Amherst. It has only 4 CS professors, but all look strong to me. There are more CS professors at Dartmouth if you are sure about CS, look over Dartmouth carefully.
(There is no such thing as an undergrad artificial intelligence major, except at Georgia Tech where students pick two threads, including “intelligence” as one of two specialties in a list of 8 specialities. Even MIT does not offer a major in AI. Carnegie Mellon now offers a statistics and machine learning major in Dietrich College of Humanities and Social Sciences. )
At Amherst, its a liberal arts environment you will get a well rounded education, including lots of mathematics, and you can probably get exposed to CS AI research at U Mass Amherst during the school year, check into research programs in CS.
https://www.cics.umass.edu/research/area/artificial-intelligence