Proof of Theorem elnn0nn
| Step | Hyp | Ref
| Expression |
| 1 | | peano2nn 4433 |
. . . . . . 7
⊢ (A
∈ ℕ → (A + 1) ∈
ℕ) |
| 2 | | 1nn 4432 |
. . . . . . . 8
⊢ 1 ∈ ℕ |
| 3 | | opreq1 3006 |
. . . . . . . . . 10
⊢ (A = 0
→ (A + 1) = (0 + 1)) |
| 4 | | 1cn 4101 |
. . . . . . . . . . 11
⊢ 1 ∈ ℂ |
| 5 | 4 | addid2 4113 |
. . . . . . . . . 10
⊢ (0 + 1) = 1 |
| 6 | 3, 5 | syl6eq 1140 |
. . . . . . . . 9
⊢ (A = 0
→ (A + 1) = 1) |
| 7 | 6 | eleq1d 1155 |
. . . . . . . 8
⊢ (A = 0
→ ((A + 1) ∈ ℕ ↔ 1
∈ ℕ)) |
| 8 | 2, 7 | mpbiri 169 |
. . . . . . 7
⊢ (A = 0
→ (A + 1) ∈ ℕ) |
| 9 | 1, 8 | jaoi 275 |
. . . . . 6
⊢ ((A
∈ ℕ ∨ A = 0) → (A + 1) ∈ ℕ) |
| 10 | 9 | a1i 7 |
. . . . 5
⊢ (A
∈ ℝ → ((A ∈ ℕ
∨ A = 0) → (A + 1) ∈ ℕ)) |
| 11 | | recnt 4097 |
. . . . . . . . 9
⊢ (A
∈ ℝ → A ∈
ℂ) |
| 12 | | 1z 4584 |
. . . . . . . . . . . 12
⊢ 1 ∈ ℤ |
| 13 | | zrevaddclt 4592 |
. . . . . . . . . . . 12
⊢ (1 ∈ ℤ → ((A ∈ ℂ ∧ (A + 1) ∈ ℤ) ↔ A ∈ ℤ)) |
| 14 | 12, 13 | ax-mp 6 |
. . . . . . . . . . 11
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℤ) ↔ A ∈ ℤ) |
| 15 | 14 | biimp 133 |
. . . . . . . . . 10
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℤ) → A ∈ ℤ) |
| 16 | 15 | exp 291 |
. . . . . . . . 9
⊢ (A
∈ ℂ → ((A + 1) ∈
ℤ → A ∈ ℤ)) |
| 17 | 11, 16 | syl 12 |
. . . . . . . 8
⊢ (A
∈ ℝ → ((A + 1) ∈
ℤ → A ∈ ℤ)) |
| 18 | | ax1re 4064 |
. . . . . . . . . . . 12
⊢ 1 ∈ ℝ |
| 19 | | ax0re 4063 |
. . . . . . . . . . . . 13
⊢ 0 ∈ ℝ |
| 20 | | leadd1t 4350 |
. . . . . . . . . . . . 13
⊢ ((0 ∈ ℝ ∧ A ∈ ℝ ∧ 1 ∈ ℝ) → (0
≤ A ↔ (0 + 1) ≤ (A + 1))) |
| 21 | 19, 20 | mp3an1 639 |
. . . . . . . . . . . 12
⊢ ((A
∈ ℝ ∧ 1 ∈ ℝ) → (0 ≤ A ↔ (0 + 1) ≤ (A + 1))) |
| 22 | 18, 21 | mpan2 519 |
. . . . . . . . . . 11
⊢ (A
∈ ℝ → (0 ≤ A ↔ (0 +
1) ≤ (A + 1))) |
| 23 | 5 | breq1i 2068 |
. . . . . . . . . . 11
⊢ ((0 + 1) ≤ (A + 1) ↔ 1 ≤ (A + 1)) |
| 24 | 22, 23 | syl6bb 414 |
. . . . . . . . . 10
⊢ (A
∈ ℝ → (0 ≤ A ↔ 1
≤ (A + 1))) |
| 25 | | leloet 4284 |
. . . . . . . . . . 11
⊢ ((0 ∈ ℝ ∧ A ∈ ℝ) → (0 ≤ A ↔ (0 < A ∨ 0 = A))) |
| 26 | 19, 25 | mpan 518 |
. . . . . . . . . 10
⊢ (A
∈ ℝ → (0 ≤ A ↔ (0
< A ∨ 0 = A))) |
| 27 | 24, 26 | bitr3d 408 |
. . . . . . . . 9
⊢ (A
∈ ℝ → (1 ≤ (A + 1)
↔ (0 < A ∨ 0 = A))) |
| 28 | 27 | biimpd 135 |
. . . . . . . 8
⊢ (A
∈ ℝ → (1 ≤ (A + 1)
→ (0 < A ∨ 0 = A))) |
| 29 | 17, 28 | anim12d 431 |
. . . . . . 7
⊢ (A
∈ ℝ → (((A + 1) ∈
ℤ ∧ 1 ≤ (A + 1)) →
(A ∈ ℤ ∧ (0 < A ∨ 0 = A)))) |
| 30 | | andi 456 |
. . . . . . . 8
⊢ ((A
∈ ℤ ∧ (0 < A ∨ 0 =
A)) ↔ ((A ∈ ℤ ∧ 0 < A) ∨ (A
∈ ℤ ∧ 0 = A))) |
| 31 | | elnnz 4572 |
. . . . . . . . 9
⊢ (A
∈ ℕ ↔ (A ∈ ℤ
∧ 0 < A)) |
| 32 | | cleqcom 1103 |
. . . . . . . . . 10
⊢ (A = 0
↔ 0 = A) |
| 33 | | 0z 4573 |
. . . . . . . . . . . 12
⊢ 0 ∈ ℤ |
| 34 | | eleq1 1149 |
. . . . . . . . . . . 12
⊢ (0 = A
→ (0 ∈ ℤ ↔ A ∈
ℤ)) |
| 35 | 33, 34 | mpbii 168 |
. . . . . . . . . . 11
⊢ (0 = A
→ A ∈ ℤ) |
| 36 | 35 | pm4.71ri 484 |
. . . . . . . . . 10
⊢ (0 = A
↔ (A ∈ ℤ ∧ 0 = A)) |
| 37 | 32, 36 | bitr 151 |
. . . . . . . . 9
⊢ (A = 0
↔ (A ∈ ℤ ∧ 0 = A)) |
| 38 | 31, 37 | orbi12i 216 |
. . . . . . . 8
⊢ ((A
∈ ℕ ∨ A = 0) ↔
((A ∈ ℤ ∧ 0 < A) ∨ (A
∈ ℤ ∧ 0 = A))) |
| 39 | 30, 38 | bitr4 154 |
. . . . . . 7
⊢ ((A
∈ ℤ ∧ (0 < A ∨ 0 =
A)) ↔ (A ∈ ℕ ∨ A = 0)) |
| 40 | 29, 39 | syl6ib 185 |
. . . . . 6
⊢ (A
∈ ℝ → (((A + 1) ∈
ℤ ∧ 1 ≤ (A + 1)) →
(A ∈ ℕ ∨ A = 0))) |
| 41 | | elnnz1 4581 |
. . . . . 6
⊢ ((A +
1) ∈ ℕ ↔ ((A + 1) ∈
ℤ ∧ 1 ≤ (A + 1))) |
| 42 | 40, 41 | syl5ib 181 |
. . . . 5
⊢ (A
∈ ℝ → ((A + 1) ∈
ℕ → (A ∈ ℕ ∨
A = 0))) |
| 43 | 10, 42 | impbid 397 |
. . . 4
⊢ (A
∈ ℝ → ((A ∈ ℕ
∨ A = 0) ↔ (A + 1) ∈ ℕ)) |
| 44 | | elnn0 4536 |
. . . 4
⊢ (A
∈ ℕ0 ↔ (A ∈
ℕ ∨ A = 0)) |
| 45 | 43, 44 | syl5bb 410 |
. . 3
⊢ (A
∈ ℝ → (A ∈
ℕ0 ↔ (A + 1) ∈
ℕ)) |
| 46 | 45 | pm5.32i 489 |
. 2
⊢ ((A
∈ ℝ ∧ A ∈
ℕ0) ↔ (A ∈
ℝ ∧ (A + 1) ∈
ℕ)) |
| 47 | | nn0ret 4542 |
. . 3
⊢ (A
∈ ℕ0 → A ∈
ℝ) |
| 48 | 47 | pm4.71ri 484 |
. 2
⊢ (A
∈ ℕ0 ↔ (A ∈
ℝ ∧ A ∈
ℕ0)) |
| 49 | | zret 4567 |
. . . . . 6
⊢ (A
∈ ℤ → A ∈
ℝ) |
| 50 | 14, 49 | sylbi 174 |
. . . . 5
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℤ) → A ∈ ℝ) |
| 51 | | nnzt 4579 |
. . . . 5
⊢ ((A +
1) ∈ ℕ → (A + 1) ∈
ℤ) |
| 52 | 50, 51 | sylan2 346 |
. . . 4
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℕ) → A ∈ ℝ) |
| 53 | | pm3.27 260 |
. . . 4
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℕ) → (A + 1) ∈
ℕ) |
| 54 | 52, 53 | jca 236 |
. . 3
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℕ) → (A ∈ ℝ ∧
(A + 1) ∈ ℕ)) |
| 55 | 11 | anim1i 269 |
. . 3
⊢ ((A
∈ ℝ ∧ (A + 1) ∈
ℕ) → (A ∈ ℂ ∧
(A + 1) ∈ ℕ)) |
| 56 | 54, 55 | impbi 139 |
. 2
⊢ ((A
∈ ℂ ∧ (A + 1) ∈
ℕ) ↔ (A ∈ ℝ ∧
(A + 1) ∈ ℕ)) |
| 57 | 46, 48, 56 | 3bitr4 158 |
1
⊢ (A
∈ ℕ0 ↔ (A ∈
ℂ ∧ (A + 1) ∈
ℕ)) |