According to the author of Genesis, this verse lists the leaders or important people in the family of Aholibamah, who was married to Esau. It's telling us about the special family members, called dukes, that came from Aholibamah and Esau.
Genesis 36:18: And these [are] the sons of Aholibamah Esau's wife; duke Jeush, duke Jaalam, duke Korah: these [were] the dukes [that came] of Aholibamah the daughter of Anah, Esau's wife.
This verse also lists the sons of Aholibamah differently, which can create confusion regarding their exact number and names across different verses.
Genesis 36:14: And these were the sons of Aholibamah, the daughter of Anah the daughter of Zibeon, Esau's wife: and she bare to Esau Jeush, and Jaalam, and Korah.