Er and Onan were sons of Judah but had died in the land of Canaan.
Judah’s sons: Er, Onan, Shelah, Perez and Zerah. Er died along with Onan in the land of Canaan. Perez’s sons were Hezron and Hamul.
From the sons of Judah (their generations, by their families, their ancestral households, the count of their names, all who would go out with the army),
The sons of Judah: Perez, Hezron, Carmi, Hur and Shobal.