ABSTRACT
Types of Numbers
Natural numbers
The set of
natural numbers
, {0, 1, 2, …}, is customarily denoted by
. Many authors do not consider 0 to be a natural number.
Integers
The set of
integers
, {0, ±1, ±2, …}, is customarily denoted by
. The
positive integers
are {1, 2, 3, …}.