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, …}.