Halayudha

Halāyudha (Sanskrit: हलायुध) wrote the Mṛtasañjīvanī, a commentary on Pingala's Chandaḥśāstra, was an Indian Mathematician and poet who lived and worked in the 10th century. The Chandaḥśāstra by the Indian lyricist Piṅgala (3rd or 2nd century BC) somewhat crypically describes a method of arranging two types of syllables to form metres of various lengths and counting them; as interpreted and elaborated by Halāyudha his "method of pyramidal expansion" (meru-prastāra) for counting metres is equivalent to Pascal's triangle.