Ram was the father of Amminadab. Amminadab was the father of Nahshon, a leader of Judah.
What does 1 Chronicles 2:10 mean?
John Gill's Exposition of the Bible
Ver. 10-12. And Ram begat Amminadab
Ram is the same with Aram, ( Matthew 1:3Matthew 1:4 ) the
genealogy is carried down from him to Jesse in the same order as
there, and in ( Ruth
4:19-22 ) only here Nahshon the son of Amminadab is called
the prince of the children of Judah;
which Kimchi and Jarchi say is written for the honour of David,
who descended from him; and Salmon his son is here called Salma.