Srimad-Bhagavatam: Canto 9 - Chapter 1 - Verse 4
जह्नोस्तु पुरुस्तस्याथ बलाकश्चात्मजोऽजक: ।तत: कुश: कुशस्यापि कुशाम्बुस्तनयो वसु: ।कुशनाभश्च चत्वारो गाधिरासीत् कुशाम्बुज: ॥ ४ ॥
jahnos tu purus tasyāthabalākaś cātmajo ’jakaḥtataḥ kuśaḥ kuśasyāpikuśāmbus tanayo vasuḥkuśanābhaś ca catvārogādhir āsīt kuśāmbujaḥ
The son of Jahnu was Puru, the son of Puru was Balāka, the son of Balāka was Ajaka, and the son of Ajaka was Kuśa. Kuśa had four sons, named Kuśāmbu, Tanaya, Vasu and Kuśanābha. The son of Kuśāmbu was Gādhi.