From Wikipedia Natural_number as well:

There is no universal agreement about whether to include zero in the set of natural numbers: some define the natural numbers to be the positive integers {1, 2, 3, ...}, while for others the term designates the non-negative integers {0, 1, 2, 3, ...}. The former definition is the traditional one, with the latter definition having first appeared in the 19th century.

In reply to Re^4: why the array index has to start at 0?? by hdb
in thread why the array index has to start at 0?? by targetsmart

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