section_path: Cardinality
section_name: Cardinality
paragraph_text: 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
  
  More technically, the cardinality of Z {\displaystyle \mathbb {Z} } is said to equal ℵ (aleph-null). The pairing between elements of Z {\displaystyle \mathbb {Z} } and N {\displaystyle \mathbb {N} } is called a bijection.