SB 9.6.5

teṣāṁ purastād abhavann
 āryāvarte nṛpā nṛpa
pañca-viṁśatiḥ paścāc ca
 trayo madhye ’pare ’nyataḥ
Synonyms: 
teṣām — among all of those sons; purastāt — on the eastern side; abhavan — they became; āryāvarte — in the place within the Himālaya and Vindhya mountains known as Āryāvarta; nṛpāḥ — kings; nṛpa — O King (Mahārāja Parīkṣit); pañca-viṁśatiḥ — twenty-five; paścāt — on the western side; ca — also; trayaḥ — three of them; madhye — in the middle (between east and west); apare — others; anyataḥ — in other places.
Translation: 
Of the one hundred sons, twenty-five became kings in the western side of Āryāvarta, a place between the Himālaya and Vindhya mountains. Another twenty-five sons became kings in the east of Āryāvarta, and the three principal sons became kings in the middle. The other sons became kings in various other places.