Matsya Purana 273.36

273.36

mahāpadmābhiṣekāttu yāvajjanmaparīkṣitaḥ.
evaṃ varṣasahasrantu jñeyaṃ pañcāśaduttaram .. 273.35

Now from Mahāpadma's inauguration up till the birth of Parīkṣit, this interval is indeed known as 1050 years (1015 according to Viṣṇu, and 1500 according to our reading).—36

Now from Mahâpadma's inauguration to Parîkṣit's birth, this interval is indeed known as 1500 years—36