Definitely call the river. Villain has taken a line that indicates he is clicking buttons and doesn't really know what he is doing and we have a strong hand. It's possible this specific villain's range is exactly 3x, but we can't know that without playing a lot with him.

Unless you have a read that he is super passive fish lets say with a AF 0,5 throught more than 100 hands i think that you can find a fold here, cause you will see sometimes A3 or some other 3x. Without a read and with this strange line i would call also. Few combos beat you and he could be a spewying away chips trying to make an orthodox bluff. Take notes on the players , see in showdown how big was his sizing on the river and what hand did he show in what specific board. That would do a huge difference sometimes.