Editing Integer (section)

==Cardinality==
The set of integers is [[countably infinite]], meaning it is possible to pair each integer with a unique natural number. An example of such a pairing is

:{{math|(0,&thinsp;1), (1,&thinsp;2), (−1,&thinsp;3), (2,&thinsp;4), (−2,&thinsp;5), }} {{math|(3,&thinsp;6), .&hairsp;.&hairsp;.&hairsp;,(1&hairsp;−&thinsp;''k'',&thinsp;2''k''&thinsp;−&hairsp;1), (''k'',&thinsp;2''k''&hairsp;), .&hairsp;.&hairsp;.}}

More technically, the [[cardinality]] of <math>\mathbb{Z}</math> is said to equal {{math|ℵ{{sub|0}}}} ([[Aleph number|aleph-null]]). The pairing between elements of <math>\mathbb{Z}</math> and <math>\mathbb{N}</math> is called a [[bijection]].