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N

The set of natural numbers (the positive integers Z⁺ 1, 2, 3, ...; OEIS A000027), denoted , also called the whole numbers. Like whole numbers, there is no general agreement on whether 0 should be included in the list of natural numbers.

Due to lack of standard terminology, the following terms are recommended in preference to "counting number," "natural number," and "whole number."

set	name	symbol
..., , , 0, 1, 2, ...	integers	Z
1, 2, 3, 4, ...	positive integers	Z⁺
0, 1, 2, 3, 4, ...	nonnegative integers	Z^*
0, , , , , ...	nonpositive integers
, , , , ...	negative integers	Z^-