Metamath Proof Explorer


Theorem eluz4eluz2

Description: An integer greater than or equal to 4 is an integer greater than or equal to 2. (Contributed by AV, 30-May-2023)

Ref Expression
Assertion eluz4eluz2 ( 𝑋 ∈ ( ℤ ‘ 4 ) → 𝑋 ∈ ( ℤ ‘ 2 ) )

Proof

Step Hyp Ref Expression
1 2z 2 ∈ ℤ
2 2re 2 ∈ ℝ
3 4re 4 ∈ ℝ
4 2lt4 2 < 4
5 2 3 4 ltleii 2 ≤ 4
6 eluzuzle ( ( 2 ∈ ℤ ∧ 2 ≤ 4 ) → ( 𝑋 ∈ ( ℤ ‘ 4 ) → 𝑋 ∈ ( ℤ ‘ 2 ) ) )
7 1 5 6 mp2an ( 𝑋 ∈ ( ℤ ‘ 4 ) → 𝑋 ∈ ( ℤ ‘ 2 ) )