numeration
Concise Oxford English Dictionary © 2008 Oxford University Press:
numeration/njuːməˈreɪʃ(ə)n/
▶noun the action or process of numbering or calculating.
■ a method of numbering or computing.
– origin ME: from L. numeratio(n-) ‘payment’ (in late L. ‘numbering’), from numerare ‘to number’.
'numeration' also found in these Oxford entries:

