Metamath Proof Explorer

Theorem zex

Description: The set of integers exists. See also zexALT . (Contributed by NM, 30-Jul-2004) (Revised by Mario Carneiro, 17-Nov-2014)

Ref Expression
Assertion zex 
|- ZZ e. _V

Proof

Step Hyp Ref Expression
1 cnex 
 |-  CC e. _V
2 zsscn 
 |-  ZZ C_ CC
3 1 2 ssexi 
 |-  ZZ e. _V