HI aspirant

The Sanskrit counting for 1 to 20 is as follows:

1. One ( ekam)

2. Two  ( dve)

3.Three  ( treeni)

4. Four  ( chatvaari)

5. Five  ( pancha)

6. Six  ( shat)

7. Seven (sapta)

8. Eight (ashta)

9. Nine (nava)

10. Ten (dasha)

11. Elelven (ekaadasha)

12. Twelve (dvaadasha)

13. Thirteen (trayodasha)

14. Fourteen (chaturdasha)

15. Fifteen (panchadasha)

16. Sixteen (shodash)

17. Seventeen (saptadasha)

18. Eighteen (ashtaadasha)

19. Nineteen (navadasha)

20. Twenty (vimshatihi)

Hope it helps!!