Manasara 7.12

7.12

triyutaṃ padmevoktaṃ tathāṣṭādaśamaṃ tathā
caturviṃśatsatriśataṃ caiva karṇāṣṭakaṃ bhavet

it is declared as Triyuta; and the eighteenth likewise
has three hundred and twenty-four [plots], and is Karṇāṣṭaka;