This is a pictograph of nine counting rods. It is the numeral nine.
Illustrative Text Reference:
Dholavira: Seal: SI. Number: 45: Acc. Number: 10922 (NB. The photograph is of the seal. Therefore, the symbol for the numeral nine is the mirror image of that seen in the photograph.): R.S.
Bisht, 2015: 8.2.3 Details of Individual Seals: Excavations at Dholavira (1989-90 to 2004-2005), p. 269:
https://www.scribd.com/document/262316120/Excavations-at-Dholavifra-1989-2005-RS-Bisht-2015: Accessed: 12 November, 2018.