Proof of Theorem elfz2nn0
Step | Hyp | Ref
| Expression |
1 | | elnn0uz 12623 |
. . . 4
⊢ (𝐾 ∈ ℕ0
↔ 𝐾 ∈
(ℤ≥‘0)) |
2 | 1 | anbi1i 624 |
. . 3
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
(ℤ≥‘𝐾)) ↔ (𝐾 ∈ (ℤ≥‘0)
∧ 𝑁 ∈
(ℤ≥‘𝐾))) |
3 | | eluznn0 12657 |
. . . . . 6
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
(ℤ≥‘𝐾)) → 𝑁 ∈
ℕ0) |
4 | | eluzle 12595 |
. . . . . . 7
⊢ (𝑁 ∈
(ℤ≥‘𝐾) → 𝐾 ≤ 𝑁) |
5 | 4 | adantl 482 |
. . . . . 6
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
(ℤ≥‘𝐾)) → 𝐾 ≤ 𝑁) |
6 | 3, 5 | jca 512 |
. . . . 5
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
(ℤ≥‘𝐾)) → (𝑁 ∈ ℕ0 ∧ 𝐾 ≤ 𝑁)) |
7 | | nn0z 12343 |
. . . . . . . 8
⊢ (𝐾 ∈ ℕ0
→ 𝐾 ∈
ℤ) |
8 | | nn0z 12343 |
. . . . . . . 8
⊢ (𝑁 ∈ ℕ0
→ 𝑁 ∈
ℤ) |
9 | | eluz 12596 |
. . . . . . . 8
⊢ ((𝐾 ∈ ℤ ∧ 𝑁 ∈ ℤ) → (𝑁 ∈
(ℤ≥‘𝐾) ↔ 𝐾 ≤ 𝑁)) |
10 | 7, 8, 9 | syl2an 596 |
. . . . . . 7
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
ℕ0) → (𝑁 ∈ (ℤ≥‘𝐾) ↔ 𝐾 ≤ 𝑁)) |
11 | 10 | biimprd 247 |
. . . . . 6
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
ℕ0) → (𝐾 ≤ 𝑁 → 𝑁 ∈ (ℤ≥‘𝐾))) |
12 | 11 | impr 455 |
. . . . 5
⊢ ((𝐾 ∈ ℕ0
∧ (𝑁 ∈
ℕ0 ∧ 𝐾
≤ 𝑁)) → 𝑁 ∈
(ℤ≥‘𝐾)) |
13 | 6, 12 | impbida 798 |
. . . 4
⊢ (𝐾 ∈ ℕ0
→ (𝑁 ∈
(ℤ≥‘𝐾) ↔ (𝑁 ∈ ℕ0 ∧ 𝐾 ≤ 𝑁))) |
14 | 13 | pm5.32i 575 |
. . 3
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
(ℤ≥‘𝐾)) ↔ (𝐾 ∈ ℕ0 ∧ (𝑁 ∈ ℕ0
∧ 𝐾 ≤ 𝑁))) |
15 | 2, 14 | bitr3i 276 |
. 2
⊢ ((𝐾 ∈
(ℤ≥‘0) ∧ 𝑁 ∈ (ℤ≥‘𝐾)) ↔ (𝐾 ∈ ℕ0 ∧ (𝑁 ∈ ℕ0
∧ 𝐾 ≤ 𝑁))) |
16 | | elfzuzb 13250 |
. 2
⊢ (𝐾 ∈ (0...𝑁) ↔ (𝐾 ∈ (ℤ≥‘0)
∧ 𝑁 ∈
(ℤ≥‘𝐾))) |
17 | | 3anass 1094 |
. 2
⊢ ((𝐾 ∈ ℕ0
∧ 𝑁 ∈
ℕ0 ∧ 𝐾
≤ 𝑁) ↔ (𝐾 ∈ ℕ0
∧ (𝑁 ∈
ℕ0 ∧ 𝐾
≤ 𝑁))) |
18 | 15, 16, 17 | 3bitr4i 303 |
1
⊢ (𝐾 ∈ (0...𝑁) ↔ (𝐾 ∈ ℕ0 ∧ 𝑁 ∈ ℕ0
∧ 𝐾 ≤ 𝑁)) |