The value of <Y>, the position of which varies in the sequences, may be the precursor of place value, in which, for example, 5, 50 and 500 represent different values according to their position, thought to have been a Sumerian invention (d'Errico et al. Reference d'Errico, Doyon and Colage2017).

The requirement, in ordinal representations of number, that the ‘special’ symbol at the ordinal position of the value being represented must be distinct from all other symbols in a sequence clearly invites a meaning to be associated with the special symbol. With such, there was no longer the need for a purely oral explanation of the system, as all of its components were self-contained to the point of being readable many thousands of years later.