| Step | Hyp | Ref
| Expression |
| 1 | | ssrab2 4080 |
. . . . . . . . . 10
⊢ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ⊆ ℕ |
| 2 | | nnuz 12921 |
. . . . . . . . . 10
⊢ ℕ =
(ℤ≥‘1) |
| 3 | 1, 2 | sseqtri 4032 |
. . . . . . . . 9
⊢ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ⊆
(ℤ≥‘1) |
| 4 | | rabn0 4389 |
. . . . . . . . . 10
⊢ ({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ≠ ∅ ↔ ∃𝑛 ∈ ℕ 𝑥 ∈ 𝐴) |
| 5 | 4 | biimpri 228 |
. . . . . . . . 9
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ≠ ∅) |
| 6 | | infssuzcl 12974 |
. . . . . . . . 9
⊢ (({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ⊆ (ℤ≥‘1)
∧ {𝑛 ∈ ℕ
∣ 𝑥 ∈ 𝐴} ≠ ∅) →
inf({𝑛 ∈ ℕ
∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}) |
| 7 | 3, 5, 6 | sylancr 587 |
. . . . . . . 8
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}) |
| 8 | | nfrab1 3457 |
. . . . . . . . . 10
⊢
Ⅎ𝑛{𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} |
| 9 | | nfcv 2905 |
. . . . . . . . . 10
⊢
Ⅎ𝑛ℝ |
| 10 | | nfcv 2905 |
. . . . . . . . . 10
⊢
Ⅎ𝑛
< |
| 11 | 8, 9, 10 | nfinf 9522 |
. . . . . . . . 9
⊢
Ⅎ𝑛inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) |
| 12 | | nfcv 2905 |
. . . . . . . . 9
⊢
Ⅎ𝑛ℕ |
| 13 | 11 | nfcsb1 3922 |
. . . . . . . . . 10
⊢
Ⅎ𝑛⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴 |
| 14 | 13 | nfcri 2897 |
. . . . . . . . 9
⊢
Ⅎ𝑛 𝑥 ∈
⦋inf({𝑛
∈ ℕ ∣ 𝑥
∈ 𝐴}, ℝ, < )
/ 𝑛⦌𝐴 |
| 15 | | csbeq1a 3913 |
. . . . . . . . . 10
⊢ (𝑛 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) → 𝐴 = ⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴) |
| 16 | 15 | eleq2d 2827 |
. . . . . . . . 9
⊢ (𝑛 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) → (𝑥 ∈ 𝐴 ↔ 𝑥 ∈ ⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴)) |
| 17 | 11, 12, 14, 16 | elrabf 3688 |
. . . . . . . 8
⊢
(inf({𝑛 ∈
ℕ ∣ 𝑥 ∈
𝐴}, ℝ, < ) ∈
{𝑛 ∈ ℕ ∣
𝑥 ∈ 𝐴} ↔ (inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈ ℕ ∧
𝑥 ∈
⦋inf({𝑛
∈ ℕ ∣ 𝑥
∈ 𝐴}, ℝ, < )
/ 𝑛⦌𝐴)) |
| 18 | 7, 17 | sylib 218 |
. . . . . . 7
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → (inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈ ℕ ∧
𝑥 ∈
⦋inf({𝑛
∈ ℕ ∣ 𝑥
∈ 𝐴}, ℝ, < )
/ 𝑛⦌𝐴)) |
| 19 | 18 | simpld 494 |
. . . . . 6
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈
ℕ) |
| 20 | 18 | simprd 495 |
. . . . . . 7
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → 𝑥 ∈ ⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴) |
| 21 | 19 | nnred 12281 |
. . . . . . . . 9
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈
ℝ) |
| 22 | 21 | ltnrd 11395 |
. . . . . . . 8
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → ¬ inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) |
| 23 | | eliun 4995 |
. . . . . . . . 9
⊢ (𝑥 ∈ ∪ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵 ↔ ∃𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝑥 ∈ 𝐵) |
| 24 | | nfcv 2905 |
. . . . . . . . . . 11
⊢
Ⅎ𝑘ℕ |
| 25 | | iundisjf.1 |
. . . . . . . . . . . 12
⊢
Ⅎ𝑘𝐴 |
| 26 | 25 | nfcri 2897 |
. . . . . . . . . . 11
⊢
Ⅎ𝑘 𝑥 ∈ 𝐴 |
| 27 | 24, 26 | nfrexw 3313 |
. . . . . . . . . 10
⊢
Ⅎ𝑘∃𝑛 ∈ ℕ 𝑥 ∈ 𝐴 |
| 28 | 26, 24 | nfrabw 3475 |
. . . . . . . . . . . 12
⊢
Ⅎ𝑘{𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} |
| 29 | | nfcv 2905 |
. . . . . . . . . . . 12
⊢
Ⅎ𝑘ℝ |
| 30 | | nfcv 2905 |
. . . . . . . . . . . 12
⊢
Ⅎ𝑘
< |
| 31 | 28, 29, 30 | nfinf 9522 |
. . . . . . . . . . 11
⊢
Ⅎ𝑘inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) |
| 32 | 31, 30, 31 | nfbr 5190 |
. . . . . . . . . 10
⊢
Ⅎ𝑘inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) |
| 33 | 21 | ad2antrr 726 |
. . . . . . . . . . . 12
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ∈
ℝ) |
| 34 | | elfzouz 13703 |
. . . . . . . . . . . . . . 15
⊢ (𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) → 𝑘 ∈
(ℤ≥‘1)) |
| 35 | 34, 2 | eleqtrrdi 2852 |
. . . . . . . . . . . . . 14
⊢ (𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) → 𝑘 ∈
ℕ) |
| 36 | 35 | ad2antlr 727 |
. . . . . . . . . . . . 13
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → 𝑘 ∈ ℕ) |
| 37 | 36 | nnred 12281 |
. . . . . . . . . . . 12
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → 𝑘 ∈ ℝ) |
| 38 | | simpr 484 |
. . . . . . . . . . . . . 14
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → 𝑥 ∈ 𝐵) |
| 39 | | nfcv 2905 |
. . . . . . . . . . . . . . 15
⊢
Ⅎ𝑛𝑘 |
| 40 | | iundisjf.2 |
. . . . . . . . . . . . . . . 16
⊢
Ⅎ𝑛𝐵 |
| 41 | 40 | nfcri 2897 |
. . . . . . . . . . . . . . 15
⊢
Ⅎ𝑛 𝑥 ∈ 𝐵 |
| 42 | | iundisjf.3 |
. . . . . . . . . . . . . . . 16
⊢ (𝑛 = 𝑘 → 𝐴 = 𝐵) |
| 43 | 42 | eleq2d 2827 |
. . . . . . . . . . . . . . 15
⊢ (𝑛 = 𝑘 → (𝑥 ∈ 𝐴 ↔ 𝑥 ∈ 𝐵)) |
| 44 | 39, 12, 41, 43 | elrabf 3688 |
. . . . . . . . . . . . . 14
⊢ (𝑘 ∈ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ↔ (𝑘 ∈ ℕ ∧ 𝑥 ∈ 𝐵)) |
| 45 | 36, 38, 44 | sylanbrc 583 |
. . . . . . . . . . . . 13
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → 𝑘 ∈ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}) |
| 46 | | infssuzle 12973 |
. . . . . . . . . . . . 13
⊢ (({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴} ⊆ (ℤ≥‘1)
∧ 𝑘 ∈ {𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}) → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ≤ 𝑘) |
| 47 | 3, 45, 46 | sylancr 587 |
. . . . . . . . . . . 12
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) ≤ 𝑘) |
| 48 | | elfzolt2 13708 |
. . . . . . . . . . . . 13
⊢ (𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) → 𝑘 < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) |
| 49 | 48 | ad2antlr 727 |
. . . . . . . . . . . 12
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → 𝑘 < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) |
| 50 | 33, 37, 33, 47, 49 | lelttrd 11419 |
. . . . . . . . . . 11
⊢
(((∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ∧ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) ∧ 𝑥 ∈ 𝐵) → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) |
| 51 | 50 | exp31 419 |
. . . . . . . . . 10
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → (𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) → (𝑥 ∈ 𝐵 → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )))) |
| 52 | 27, 32, 51 | rexlimd 3266 |
. . . . . . . . 9
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → (∃𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝑥 ∈ 𝐵 → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) |
| 53 | 23, 52 | biimtrid 242 |
. . . . . . . 8
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → (𝑥 ∈ ∪
𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵 → inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) < inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) |
| 54 | 22, 53 | mtod 198 |
. . . . . . 7
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → ¬ 𝑥 ∈ ∪
𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵) |
| 55 | 20, 54 | eldifd 3962 |
. . . . . 6
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → 𝑥 ∈ (⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵)) |
| 56 | | csbeq1 3902 |
. . . . . . . . 9
⊢ (𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) →
⦋𝑚 / 𝑛⦌𝐴 = ⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴) |
| 57 | 31 | nfeq2 2923 |
. . . . . . . . . 10
⊢
Ⅎ𝑘 𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) |
| 58 | | nfcv 2905 |
. . . . . . . . . 10
⊢
Ⅎ𝑘(1..^𝑚) |
| 59 | | nfcv 2905 |
. . . . . . . . . . 11
⊢
Ⅎ𝑘1 |
| 60 | | nfcv 2905 |
. . . . . . . . . . 11
⊢
Ⅎ𝑘..^ |
| 61 | 59, 60, 31 | nfov 7461 |
. . . . . . . . . 10
⊢
Ⅎ𝑘(1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < )) |
| 62 | | oveq2 7439 |
. . . . . . . . . 10
⊢ (𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) → (1..^𝑚) = (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))) |
| 63 | | eqidd 2738 |
. . . . . . . . . 10
⊢ (𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) → 𝐵 = 𝐵) |
| 64 | 57, 58, 61, 62, 63 | iuneq12df 5018 |
. . . . . . . . 9
⊢ (𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) → ∪ 𝑘 ∈ (1..^𝑚)𝐵 = ∪ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵) |
| 65 | 56, 64 | difeq12d 4127 |
. . . . . . . 8
⊢ (𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) →
(⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵) = (⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵)) |
| 66 | 65 | eleq2d 2827 |
. . . . . . 7
⊢ (𝑚 = inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) → (𝑥 ∈ (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵) ↔ 𝑥 ∈ (⦋inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ) / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵))) |
| 67 | 66 | rspcev 3622 |
. . . . . 6
⊢
((inf({𝑛 ∈
ℕ ∣ 𝑥 ∈
𝐴}, ℝ, < ) ∈
ℕ ∧ 𝑥 ∈
(⦋inf({𝑛
∈ ℕ ∣ 𝑥
∈ 𝐴}, ℝ, < )
/ 𝑛⦌𝐴 ∖ ∪ 𝑘 ∈ (1..^inf({𝑛 ∈ ℕ ∣ 𝑥 ∈ 𝐴}, ℝ, < ))𝐵)) → ∃𝑚 ∈ ℕ 𝑥 ∈ (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵)) |
| 68 | 19, 55, 67 | syl2anc 584 |
. . . . 5
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → ∃𝑚 ∈ ℕ 𝑥 ∈ (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵)) |
| 69 | | nfv 1914 |
. . . . . 6
⊢
Ⅎ𝑚 𝑥 ∈ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵) |
| 70 | | nfcsb1v 3923 |
. . . . . . . 8
⊢
Ⅎ𝑛⦋𝑚 / 𝑛⦌𝐴 |
| 71 | | nfcv 2905 |
. . . . . . . . 9
⊢
Ⅎ𝑛(1..^𝑚) |
| 72 | 71, 40 | nfiun 5023 |
. . . . . . . 8
⊢
Ⅎ𝑛∪ 𝑘 ∈ (1..^𝑚)𝐵 |
| 73 | 70, 72 | nfdif 4129 |
. . . . . . 7
⊢
Ⅎ𝑛(⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵) |
| 74 | 73 | nfcri 2897 |
. . . . . 6
⊢
Ⅎ𝑛 𝑥 ∈ (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵) |
| 75 | | csbeq1a 3913 |
. . . . . . . 8
⊢ (𝑛 = 𝑚 → 𝐴 = ⦋𝑚 / 𝑛⦌𝐴) |
| 76 | | oveq2 7439 |
. . . . . . . . 9
⊢ (𝑛 = 𝑚 → (1..^𝑛) = (1..^𝑚)) |
| 77 | 76 | iuneq1d 5019 |
. . . . . . . 8
⊢ (𝑛 = 𝑚 → ∪
𝑘 ∈ (1..^𝑛)𝐵 = ∪ 𝑘 ∈ (1..^𝑚)𝐵) |
| 78 | 75, 77 | difeq12d 4127 |
. . . . . . 7
⊢ (𝑛 = 𝑚 → (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵) = (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵)) |
| 79 | 78 | eleq2d 2827 |
. . . . . 6
⊢ (𝑛 = 𝑚 → (𝑥 ∈ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵) ↔ 𝑥 ∈ (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵))) |
| 80 | 69, 74, 79 | cbvrexw 3307 |
. . . . 5
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ (𝐴 ∖ ∪ 𝑘 ∈ (1..^𝑛)𝐵) ↔ ∃𝑚 ∈ ℕ 𝑥 ∈ (⦋𝑚 / 𝑛⦌𝐴 ∖ ∪
𝑘 ∈ (1..^𝑚)𝐵)) |
| 81 | 68, 80 | sylibr 234 |
. . . 4
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 → ∃𝑛 ∈ ℕ 𝑥 ∈ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵)) |
| 82 | | eldifi 4131 |
. . . . 5
⊢ (𝑥 ∈ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵) → 𝑥 ∈ 𝐴) |
| 83 | 82 | reximi 3084 |
. . . 4
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ (𝐴 ∖ ∪ 𝑘 ∈ (1..^𝑛)𝐵) → ∃𝑛 ∈ ℕ 𝑥 ∈ 𝐴) |
| 84 | 81, 83 | impbii 209 |
. . 3
⊢
(∃𝑛 ∈
ℕ 𝑥 ∈ 𝐴 ↔ ∃𝑛 ∈ ℕ 𝑥 ∈ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵)) |
| 85 | | eliun 4995 |
. . 3
⊢ (𝑥 ∈ ∪ 𝑛 ∈ ℕ 𝐴 ↔ ∃𝑛 ∈ ℕ 𝑥 ∈ 𝐴) |
| 86 | | eliun 4995 |
. . 3
⊢ (𝑥 ∈ ∪ 𝑛 ∈ ℕ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵) ↔ ∃𝑛 ∈ ℕ 𝑥 ∈ (𝐴 ∖ ∪
𝑘 ∈ (1..^𝑛)𝐵)) |
| 87 | 84, 85, 86 | 3bitr4i 303 |
. 2
⊢ (𝑥 ∈ ∪ 𝑛 ∈ ℕ 𝐴 ↔ 𝑥 ∈ ∪
𝑛 ∈ ℕ (𝐴 ∖ ∪ 𝑘 ∈ (1..^𝑛)𝐵)) |
| 88 | 87 | eqriv 2734 |
1
⊢ ∪ 𝑛 ∈ ℕ 𝐴 = ∪ 𝑛 ∈ ℕ (𝐴 ∖ ∪ 𝑘 ∈ (1..^𝑛)𝐵) |