The corpus, every claim citable.

The Yajurveda Saṁhitā (Vājasaneyī xvii.2, c. 1200–800 BCE) lists thirteen decimal denominations — eka (1) through parārdha (10¹²) — each ten times the preceding; the same list recurs in the Taittirīya Saṁhitā. Datta & Singh (1938) contrast this with Greek terminology, which stopped at the myriad (10⁴), and Roman, at mille (10³). Named decuple ranks are a documented Vedic-era feature of Sanskrit, many centuries before written place-value numerals.

History of Hindu Mathematics — A Source Book · 1938