Step |
Hyp |
Ref |
Expression |
1 |
|
uzinf.1 |
⊢ 𝑍 = ( ℤ≥ ‘ 𝑀 ) |
2 |
|
fveq2 |
⊢ ( 𝑀 = if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) → ( ℤ≥ ‘ 𝑀 ) = ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ) |
3 |
1 2
|
eqtrid |
⊢ ( 𝑀 = if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) → 𝑍 = ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ) |
4 |
3
|
breq1d |
⊢ ( 𝑀 = if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) → ( 𝑍 ≈ ω ↔ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ≈ ω ) ) |
5 |
|
omex |
⊢ ω ∈ V |
6 |
|
fvex |
⊢ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ∈ V |
7 |
|
0z |
⊢ 0 ∈ ℤ |
8 |
7
|
elimel |
⊢ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ∈ ℤ |
9 |
|
eqid |
⊢ ( rec ( ( 𝑥 ∈ V ↦ ( 𝑥 + 1 ) ) , if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ↾ ω ) = ( rec ( ( 𝑥 ∈ V ↦ ( 𝑥 + 1 ) ) , if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ↾ ω ) |
10 |
8 9
|
om2uzf1oi |
⊢ ( rec ( ( 𝑥 ∈ V ↦ ( 𝑥 + 1 ) ) , if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ↾ ω ) : ω –1-1-onto→ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) |
11 |
|
f1oen2g |
⊢ ( ( ω ∈ V ∧ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ∈ V ∧ ( rec ( ( 𝑥 ∈ V ↦ ( 𝑥 + 1 ) ) , if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ↾ ω ) : ω –1-1-onto→ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ) → ω ≈ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ) |
12 |
5 6 10 11
|
mp3an |
⊢ ω ≈ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) |
13 |
12
|
ensymi |
⊢ ( ℤ≥ ‘ if ( 𝑀 ∈ ℤ , 𝑀 , 0 ) ) ≈ ω |
14 |
4 13
|
dedth |
⊢ ( 𝑀 ∈ ℤ → 𝑍 ≈ ω ) |