Metamath Proof Explorer


Theorem zct

Description: The set of integer numbers is countable. (Contributed by Glauco Siliprandi, 17-Aug-2020)

Ref Expression
Assertion zct ℤ ≼ ω

Proof

Step Hyp Ref Expression
1 zenom ℤ ≈ ω
2 endom ( ℤ ≈ ω → ℤ ≼ ω )
3 1 2 ax-mp ℤ ≼ ω