来=COME e.g. 有空来玩啊 去=GO e.g. 你可以回去了

来来来，means "come on" the usage is for warmfuly asking somebody come here or join some action, like playing basketball...

Come over, Or Come on.

来来来 1.用于唤起别人注意。例句：来来来...让一让啦， 2.用于招呼别人住你这边走。来来来，请大家一个跟着一个，这边走。

I'm sure a dictionary will help you well with that.