| Step | Hyp | Ref
| Expression |
| 1 | | hasheqf1o 13137 |
. . . 4
⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) →
((#‘𝐴) =
(#‘𝐵) ↔
∃𝑓 𝑓:𝐴–1-1-onto→𝐵)) |
| 2 | 1 | biimprd 238 |
. . 3
⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) →
(∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵))) |
| 3 | 2 | a1d 25 |
. 2
⊢ ((𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) → ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵)))) |
| 4 | | fiinfnf1o 13138 |
. . . 4
⊢ ((𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) → ¬
∃𝑓 𝑓:𝐴–1-1-onto→𝐵) |
| 5 | 4 | pm2.21d 118 |
. . 3
⊢ ((𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) →
(∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵))) |
| 6 | 5 | a1d 25 |
. 2
⊢ ((𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) → ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵)))) |
| 7 | | fiinfnf1o 13138 |
. . . 4
⊢ ((𝐵 ∈ Fin ∧ ¬ 𝐴 ∈ Fin) → ¬
∃𝑔 𝑔:𝐵–1-1-onto→𝐴) |
| 8 | | 19.41v 1914 |
. . . . . . 7
⊢
(∃𝑓(𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) ↔ (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊))) |
| 9 | | f1orel 6140 |
. . . . . . . . . . . . 13
⊢ (𝑓:𝐴–1-1-onto→𝐵 → Rel 𝑓) |
| 10 | 9 | adantr 481 |
. . . . . . . . . . . 12
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → Rel 𝑓) |
| 11 | | f1ocnvb 6150 |
. . . . . . . . . . . 12
⊢ (Rel
𝑓 → (𝑓:𝐴–1-1-onto→𝐵 ↔ ◡𝑓:𝐵–1-1-onto→𝐴)) |
| 12 | 10, 11 | syl 17 |
. . . . . . . . . . 11
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (𝑓:𝐴–1-1-onto→𝐵 ↔ ◡𝑓:𝐵–1-1-onto→𝐴)) |
| 13 | | f1of 6137 |
. . . . . . . . . . . . . . 15
⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝑓:𝐴⟶𝐵) |
| 14 | 13 | adantr 481 |
. . . . . . . . . . . . . 14
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → 𝑓:𝐴⟶𝐵) |
| 15 | | simprl 794 |
. . . . . . . . . . . . . 14
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → 𝐴 ∈ 𝑉) |
| 16 | | simprr 796 |
. . . . . . . . . . . . . 14
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → 𝐵 ∈ 𝑊) |
| 17 | | fex2 7121 |
. . . . . . . . . . . . . 14
⊢ ((𝑓:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → 𝑓 ∈ V) |
| 18 | 14, 15, 16, 17 | syl3anc 1326 |
. . . . . . . . . . . . 13
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → 𝑓 ∈ V) |
| 19 | | cnvexg 7112 |
. . . . . . . . . . . . 13
⊢ (𝑓 ∈ V → ◡𝑓 ∈ V) |
| 20 | | f1oeq1 6127 |
. . . . . . . . . . . . . 14
⊢ (𝑔 = ◡𝑓 → (𝑔:𝐵–1-1-onto→𝐴 ↔ ◡𝑓:𝐵–1-1-onto→𝐴)) |
| 21 | 20 | spcegv 3294 |
. . . . . . . . . . . . 13
⊢ (◡𝑓 ∈ V → (◡𝑓:𝐵–1-1-onto→𝐴 → ∃𝑔 𝑔:𝐵–1-1-onto→𝐴)) |
| 22 | 18, 19, 21 | 3syl 18 |
. . . . . . . . . . . 12
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (◡𝑓:𝐵–1-1-onto→𝐴 → ∃𝑔 𝑔:𝐵–1-1-onto→𝐴)) |
| 23 | | pm2.24 121 |
. . . . . . . . . . . 12
⊢
(∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵))) |
| 24 | 22, 23 | syl6 35 |
. . . . . . . . . . 11
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (◡𝑓:𝐵–1-1-onto→𝐴 → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵)))) |
| 25 | 12, 24 | sylbid 230 |
. . . . . . . . . 10
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (𝑓:𝐴–1-1-onto→𝐵 → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵)))) |
| 26 | 25 | com12 32 |
. . . . . . . . 9
⊢ (𝑓:𝐴–1-1-onto→𝐵 → ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵)))) |
| 27 | 26 | anabsi5 858 |
. . . . . . . 8
⊢ ((𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵))) |
| 28 | 27 | exlimiv 1858 |
. . . . . . 7
⊢
(∃𝑓(𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵))) |
| 29 | 8, 28 | sylbir 225 |
. . . . . 6
⊢
((∃𝑓 𝑓:𝐴–1-1-onto→𝐵 ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵))) |
| 30 | 29 | ex 450 |
. . . . 5
⊢
(∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (¬ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → (#‘𝐴) = (#‘𝐵)))) |
| 31 | 30 | com13 88 |
. . . 4
⊢ (¬
∃𝑔 𝑔:𝐵–1-1-onto→𝐴 → ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵)))) |
| 32 | 7, 31 | syl 17 |
. . 3
⊢ ((𝐵 ∈ Fin ∧ ¬ 𝐴 ∈ Fin) → ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵)))) |
| 33 | 32 | ancoms 469 |
. 2
⊢ ((¬
𝐴 ∈ Fin ∧ 𝐵 ∈ Fin) → ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵)))) |
| 34 | | hashinf 13122 |
. . . . . . . . . 10
⊢ ((𝐴 ∈ 𝑉 ∧ ¬ 𝐴 ∈ Fin) → (#‘𝐴) = +∞) |
| 35 | 34 | expcom 451 |
. . . . . . . . 9
⊢ (¬
𝐴 ∈ Fin → (𝐴 ∈ 𝑉 → (#‘𝐴) = +∞)) |
| 36 | 35 | adantr 481 |
. . . . . . . 8
⊢ ((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) → (𝐴 ∈ 𝑉 → (#‘𝐴) = +∞)) |
| 37 | 36 | com12 32 |
. . . . . . 7
⊢ (𝐴 ∈ 𝑉 → ((¬ 𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) → (#‘𝐴) = +∞)) |
| 38 | 37 | adantr 481 |
. . . . . 6
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((¬ 𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) → (#‘𝐴) = +∞)) |
| 39 | 38 | impcom 446 |
. . . . 5
⊢ (((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (#‘𝐴) = +∞) |
| 40 | | hashinf 13122 |
. . . . . . . . . 10
⊢ ((𝐵 ∈ 𝑊 ∧ ¬ 𝐵 ∈ Fin) → (#‘𝐵) = +∞) |
| 41 | 40 | expcom 451 |
. . . . . . . . 9
⊢ (¬
𝐵 ∈ Fin → (𝐵 ∈ 𝑊 → (#‘𝐵) = +∞)) |
| 42 | 41 | adantl 482 |
. . . . . . . 8
⊢ ((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) → (𝐵 ∈ 𝑊 → (#‘𝐵) = +∞)) |
| 43 | 42 | com12 32 |
. . . . . . 7
⊢ (𝐵 ∈ 𝑊 → ((¬ 𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) → (#‘𝐵) = +∞)) |
| 44 | 43 | adantl 482 |
. . . . . 6
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → ((¬ 𝐴 ∈ Fin ∧ ¬ 𝐵 ∈ Fin) → (#‘𝐵) = +∞)) |
| 45 | 44 | impcom 446 |
. . . . 5
⊢ (((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (#‘𝐵) = +∞) |
| 46 | 39, 45 | eqtr4d 2659 |
. . . 4
⊢ (((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (#‘𝐴) = (#‘𝐵)) |
| 47 | 46 | a1d 25 |
. . 3
⊢ (((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) ∧ (𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊)) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵))) |
| 48 | 47 | ex 450 |
. 2
⊢ ((¬
𝐴 ∈ Fin ∧ ¬
𝐵 ∈ Fin) →
((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵)))) |
| 49 | 3, 6, 33, 48 | 4cases 990 |
1
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (#‘𝐴) = (#‘𝐵))) |