Proof of Theorem 2sqlem8a
| Step | Hyp | Ref
| Expression |
| 1 | | 2sqlem8.1 |
. . . 4
⊢ (𝜑 → 𝐴 ∈ ℤ) |
| 2 | | 2sqlem8.m |
. . . . . 6
⊢ (𝜑 → 𝑀 ∈
(ℤ≥‘2)) |
| 3 | | eluz2b3 12964 |
. . . . . 6
⊢ (𝑀 ∈
(ℤ≥‘2) ↔ (𝑀 ∈ ℕ ∧ 𝑀 ≠ 1)) |
| 4 | 2, 3 | sylib 218 |
. . . . 5
⊢ (𝜑 → (𝑀 ∈ ℕ ∧ 𝑀 ≠ 1)) |
| 5 | 4 | simpld 494 |
. . . 4
⊢ (𝜑 → 𝑀 ∈ ℕ) |
| 6 | | 2sqlem8.c |
. . . 4
⊢ 𝐶 = (((𝐴 + (𝑀 / 2)) mod 𝑀) − (𝑀 / 2)) |
| 7 | 1, 5, 6 | 4sqlem5 16980 |
. . 3
⊢ (𝜑 → (𝐶 ∈ ℤ ∧ ((𝐴 − 𝐶) / 𝑀) ∈ ℤ)) |
| 8 | 7 | simpld 494 |
. 2
⊢ (𝜑 → 𝐶 ∈ ℤ) |
| 9 | | 2sqlem8.2 |
. . . 4
⊢ (𝜑 → 𝐵 ∈ ℤ) |
| 10 | | 2sqlem8.d |
. . . 4
⊢ 𝐷 = (((𝐵 + (𝑀 / 2)) mod 𝑀) − (𝑀 / 2)) |
| 11 | 9, 5, 10 | 4sqlem5 16980 |
. . 3
⊢ (𝜑 → (𝐷 ∈ ℤ ∧ ((𝐵 − 𝐷) / 𝑀) ∈ ℤ)) |
| 12 | 11 | simpld 494 |
. 2
⊢ (𝜑 → 𝐷 ∈ ℤ) |
| 13 | 4 | simprd 495 |
. . . 4
⊢ (𝜑 → 𝑀 ≠ 1) |
| 14 | | simpr 484 |
. . . . . . . . . 10
⊢ ((𝜑 ∧ (𝐶↑2) = 0) → (𝐶↑2) = 0) |
| 15 | 1, 5, 6, 14 | 4sqlem9 16984 |
. . . . . . . . 9
⊢ ((𝜑 ∧ (𝐶↑2) = 0) → (𝑀↑2) ∥ (𝐴↑2)) |
| 16 | 15 | ex 412 |
. . . . . . . 8
⊢ (𝜑 → ((𝐶↑2) = 0 → (𝑀↑2) ∥ (𝐴↑2))) |
| 17 | | eluzelz 12888 |
. . . . . . . . . 10
⊢ (𝑀 ∈
(ℤ≥‘2) → 𝑀 ∈ ℤ) |
| 18 | 2, 17 | syl 17 |
. . . . . . . . 9
⊢ (𝜑 → 𝑀 ∈ ℤ) |
| 19 | | dvdssq 16604 |
. . . . . . . . 9
⊢ ((𝑀 ∈ ℤ ∧ 𝐴 ∈ ℤ) → (𝑀 ∥ 𝐴 ↔ (𝑀↑2) ∥ (𝐴↑2))) |
| 20 | 18, 1, 19 | syl2anc 584 |
. . . . . . . 8
⊢ (𝜑 → (𝑀 ∥ 𝐴 ↔ (𝑀↑2) ∥ (𝐴↑2))) |
| 21 | 16, 20 | sylibrd 259 |
. . . . . . 7
⊢ (𝜑 → ((𝐶↑2) = 0 → 𝑀 ∥ 𝐴)) |
| 22 | | simpr 484 |
. . . . . . . . . 10
⊢ ((𝜑 ∧ (𝐷↑2) = 0) → (𝐷↑2) = 0) |
| 23 | 9, 5, 10, 22 | 4sqlem9 16984 |
. . . . . . . . 9
⊢ ((𝜑 ∧ (𝐷↑2) = 0) → (𝑀↑2) ∥ (𝐵↑2)) |
| 24 | 23 | ex 412 |
. . . . . . . 8
⊢ (𝜑 → ((𝐷↑2) = 0 → (𝑀↑2) ∥ (𝐵↑2))) |
| 25 | | dvdssq 16604 |
. . . . . . . . 9
⊢ ((𝑀 ∈ ℤ ∧ 𝐵 ∈ ℤ) → (𝑀 ∥ 𝐵 ↔ (𝑀↑2) ∥ (𝐵↑2))) |
| 26 | 18, 9, 25 | syl2anc 584 |
. . . . . . . 8
⊢ (𝜑 → (𝑀 ∥ 𝐵 ↔ (𝑀↑2) ∥ (𝐵↑2))) |
| 27 | 24, 26 | sylibrd 259 |
. . . . . . 7
⊢ (𝜑 → ((𝐷↑2) = 0 → 𝑀 ∥ 𝐵)) |
| 28 | | 2sqlem8.3 |
. . . . . . . . . . 11
⊢ (𝜑 → (𝐴 gcd 𝐵) = 1) |
| 29 | | ax-1ne0 11224 |
. . . . . . . . . . . 12
⊢ 1 ≠
0 |
| 30 | 29 | a1i 11 |
. . . . . . . . . . 11
⊢ (𝜑 → 1 ≠ 0) |
| 31 | 28, 30 | eqnetrd 3008 |
. . . . . . . . . 10
⊢ (𝜑 → (𝐴 gcd 𝐵) ≠ 0) |
| 32 | 31 | neneqd 2945 |
. . . . . . . . 9
⊢ (𝜑 → ¬ (𝐴 gcd 𝐵) = 0) |
| 33 | | gcdeq0 16554 |
. . . . . . . . . 10
⊢ ((𝐴 ∈ ℤ ∧ 𝐵 ∈ ℤ) → ((𝐴 gcd 𝐵) = 0 ↔ (𝐴 = 0 ∧ 𝐵 = 0))) |
| 34 | 1, 9, 33 | syl2anc 584 |
. . . . . . . . 9
⊢ (𝜑 → ((𝐴 gcd 𝐵) = 0 ↔ (𝐴 = 0 ∧ 𝐵 = 0))) |
| 35 | 32, 34 | mtbid 324 |
. . . . . . . 8
⊢ (𝜑 → ¬ (𝐴 = 0 ∧ 𝐵 = 0)) |
| 36 | | dvdslegcd 16541 |
. . . . . . . 8
⊢ (((𝑀 ∈ ℤ ∧ 𝐴 ∈ ℤ ∧ 𝐵 ∈ ℤ) ∧ ¬
(𝐴 = 0 ∧ 𝐵 = 0)) → ((𝑀 ∥ 𝐴 ∧ 𝑀 ∥ 𝐵) → 𝑀 ≤ (𝐴 gcd 𝐵))) |
| 37 | 18, 1, 9, 35, 36 | syl31anc 1375 |
. . . . . . 7
⊢ (𝜑 → ((𝑀 ∥ 𝐴 ∧ 𝑀 ∥ 𝐵) → 𝑀 ≤ (𝐴 gcd 𝐵))) |
| 38 | 21, 27, 37 | syl2and 608 |
. . . . . 6
⊢ (𝜑 → (((𝐶↑2) = 0 ∧ (𝐷↑2) = 0) → 𝑀 ≤ (𝐴 gcd 𝐵))) |
| 39 | 28 | breq2d 5155 |
. . . . . . 7
⊢ (𝜑 → (𝑀 ≤ (𝐴 gcd 𝐵) ↔ 𝑀 ≤ 1)) |
| 40 | | nnle1eq1 12296 |
. . . . . . . 8
⊢ (𝑀 ∈ ℕ → (𝑀 ≤ 1 ↔ 𝑀 = 1)) |
| 41 | 5, 40 | syl 17 |
. . . . . . 7
⊢ (𝜑 → (𝑀 ≤ 1 ↔ 𝑀 = 1)) |
| 42 | 39, 41 | bitrd 279 |
. . . . . 6
⊢ (𝜑 → (𝑀 ≤ (𝐴 gcd 𝐵) ↔ 𝑀 = 1)) |
| 43 | 38, 42 | sylibd 239 |
. . . . 5
⊢ (𝜑 → (((𝐶↑2) = 0 ∧ (𝐷↑2) = 0) → 𝑀 = 1)) |
| 44 | 43 | necon3ad 2953 |
. . . 4
⊢ (𝜑 → (𝑀 ≠ 1 → ¬ ((𝐶↑2) = 0 ∧ (𝐷↑2) = 0))) |
| 45 | 13, 44 | mpd 15 |
. . 3
⊢ (𝜑 → ¬ ((𝐶↑2) = 0 ∧ (𝐷↑2) = 0)) |
| 46 | 8 | zcnd 12723 |
. . . . 5
⊢ (𝜑 → 𝐶 ∈ ℂ) |
| 47 | | sqeq0 14160 |
. . . . 5
⊢ (𝐶 ∈ ℂ → ((𝐶↑2) = 0 ↔ 𝐶 = 0)) |
| 48 | 46, 47 | syl 17 |
. . . 4
⊢ (𝜑 → ((𝐶↑2) = 0 ↔ 𝐶 = 0)) |
| 49 | 12 | zcnd 12723 |
. . . . 5
⊢ (𝜑 → 𝐷 ∈ ℂ) |
| 50 | | sqeq0 14160 |
. . . . 5
⊢ (𝐷 ∈ ℂ → ((𝐷↑2) = 0 ↔ 𝐷 = 0)) |
| 51 | 49, 50 | syl 17 |
. . . 4
⊢ (𝜑 → ((𝐷↑2) = 0 ↔ 𝐷 = 0)) |
| 52 | 48, 51 | anbi12d 632 |
. . 3
⊢ (𝜑 → (((𝐶↑2) = 0 ∧ (𝐷↑2) = 0) ↔ (𝐶 = 0 ∧ 𝐷 = 0))) |
| 53 | 45, 52 | mtbid 324 |
. 2
⊢ (𝜑 → ¬ (𝐶 = 0 ∧ 𝐷 = 0)) |
| 54 | | gcdn0cl 16539 |
. 2
⊢ (((𝐶 ∈ ℤ ∧ 𝐷 ∈ ℤ) ∧ ¬
(𝐶 = 0 ∧ 𝐷 = 0)) → (𝐶 gcd 𝐷) ∈ ℕ) |
| 55 | 8, 12, 53, 54 | syl21anc 838 |
1
⊢ (𝜑 → (𝐶 gcd 𝐷) ∈ ℕ) |