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| Mirrors > Home > MPE Home > Th. List > iunctb | Structured version Visualization version GIF version | ||
| Description: The countable union of countable sets is countable (indexed union version of unictb 10616). (Contributed by Mario Carneiro, 18-Jan-2014.) | 
| Ref | Expression | 
|---|---|
| iunctb | ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 𝐵 ≼ ω) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | eqid 2736 | . . 3 ⊢ ∪ 𝑥 ∈ 𝐴 ({𝑥} × 𝐵) = ∪ 𝑥 ∈ 𝐴 ({𝑥} × 𝐵) | |
| 2 | simpl 482 | . . . 4 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → 𝐴 ≼ ω) | |
| 3 | ctex 9005 | . . . . . . 7 ⊢ (𝐴 ≼ ω → 𝐴 ∈ V) | |
| 4 | 3 | adantr 480 | . . . . . 6 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → 𝐴 ∈ V) | 
| 5 | ovex 7465 | . . . . . . 7 ⊢ (ω ↑m 𝐵) ∈ V | |
| 6 | 5 | rgenw 3064 | . . . . . 6 ⊢ ∀𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ V | 
| 7 | iunexg 7989 | . . . . . 6 ⊢ ((𝐴 ∈ V ∧ ∀𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ V) → ∪ 𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ V) | |
| 8 | 4, 6, 7 | sylancl 586 | . . . . 5 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ V) | 
| 9 | acncc 10481 | . . . . 5 ⊢ AC ω = V | |
| 10 | 8, 9 | eleqtrrdi 2851 | . . . 4 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ AC ω) | 
| 11 | acndom 10092 | . . . 4 ⊢ (𝐴 ≼ ω → (∪ 𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ AC ω → ∪ 𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ AC 𝐴)) | |
| 12 | 2, 10, 11 | sylc 65 | . . 3 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 (ω ↑m 𝐵) ∈ AC 𝐴) | 
| 13 | simpr 484 | . . 3 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) | |
| 14 | omex 9684 | . . . . . 6 ⊢ ω ∈ V | |
| 15 | xpdom1g 9110 | . . . . . 6 ⊢ ((ω ∈ V ∧ 𝐴 ≼ ω) → (𝐴 × ω) ≼ (ω × ω)) | |
| 16 | 14, 2, 15 | sylancr 587 | . . . . 5 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → (𝐴 × ω) ≼ (ω × ω)) | 
| 17 | xpomen 10056 | . . . . 5 ⊢ (ω × ω) ≈ ω | |
| 18 | domentr 9054 | . . . . 5 ⊢ (((𝐴 × ω) ≼ (ω × ω) ∧ (ω × ω) ≈ ω) → (𝐴 × ω) ≼ ω) | |
| 19 | 16, 17, 18 | sylancl 586 | . . . 4 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → (𝐴 × ω) ≼ ω) | 
| 20 | ctex 9005 | . . . . . . 7 ⊢ (𝐵 ≼ ω → 𝐵 ∈ V) | |
| 21 | 20 | ralimi 3082 | . . . . . 6 ⊢ (∀𝑥 ∈ 𝐴 𝐵 ≼ ω → ∀𝑥 ∈ 𝐴 𝐵 ∈ V) | 
| 22 | iunexg 7989 | . . . . . 6 ⊢ ((𝐴 ∈ V ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ V) → ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V) | |
| 23 | 3, 21, 22 | syl2an 596 | . . . . 5 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V) | 
| 24 | omelon 9687 | . . . . . 6 ⊢ ω ∈ On | |
| 25 | onenon 9990 | . . . . . 6 ⊢ (ω ∈ On → ω ∈ dom card) | |
| 26 | 24, 25 | ax-mp 5 | . . . . 5 ⊢ ω ∈ dom card | 
| 27 | numacn 10090 | . . . . 5 ⊢ (∪ 𝑥 ∈ 𝐴 𝐵 ∈ V → (ω ∈ dom card → ω ∈ AC ∪ 𝑥 ∈ 𝐴 𝐵)) | |
| 28 | 23, 26, 27 | mpisyl 21 | . . . 4 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ω ∈ AC ∪ 𝑥 ∈ 𝐴 𝐵) | 
| 29 | acndom2 10095 | . . . 4 ⊢ ((𝐴 × ω) ≼ ω → (ω ∈ AC ∪ 𝑥 ∈ 𝐴 𝐵 → (𝐴 × ω) ∈ AC ∪ 𝑥 ∈ 𝐴 𝐵)) | |
| 30 | 19, 28, 29 | sylc 65 | . . 3 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → (𝐴 × ω) ∈ AC ∪ 𝑥 ∈ 𝐴 𝐵) | 
| 31 | 1, 12, 13, 30 | iundomg 10582 | . 2 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 𝐵 ≼ (𝐴 × ω)) | 
| 32 | domtr 9048 | . 2 ⊢ ((∪ 𝑥 ∈ 𝐴 𝐵 ≼ (𝐴 × ω) ∧ (𝐴 × ω) ≼ ω) → ∪ 𝑥 ∈ 𝐴 𝐵 ≼ ω) | |
| 33 | 31, 19, 32 | syl2anc 584 | 1 ⊢ ((𝐴 ≼ ω ∧ ∀𝑥 ∈ 𝐴 𝐵 ≼ ω) → ∪ 𝑥 ∈ 𝐴 𝐵 ≼ ω) | 
| Colors of variables: wff setvar class | 
| Syntax hints: → wi 4 ∧ wa 395 ∈ wcel 2107 ∀wral 3060 Vcvv 3479 {csn 4625 ∪ ciun 4990 class class class wbr 5142 × cxp 5682 dom cdm 5684 Oncon0 6383 (class class class)co 7432 ωcom 7888 ↑m cmap 8867 ≈ cen 8983 ≼ cdom 8984 cardccrd 9976 AC wacn 9979 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1794 ax-4 1808 ax-5 1909 ax-6 1966 ax-7 2006 ax-8 2109 ax-9 2117 ax-10 2140 ax-11 2156 ax-12 2176 ax-ext 2707 ax-rep 5278 ax-sep 5295 ax-nul 5305 ax-pow 5364 ax-pr 5431 ax-un 7756 ax-inf2 9682 ax-cc 10476 | 
| This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3or 1087 df-3an 1088 df-tru 1542 df-fal 1552 df-ex 1779 df-nf 1783 df-sb 2064 df-mo 2539 df-eu 2568 df-clab 2714 df-cleq 2728 df-clel 2815 df-nfc 2891 df-ne 2940 df-ral 3061 df-rex 3070 df-rmo 3379 df-reu 3380 df-rab 3436 df-v 3481 df-sbc 3788 df-csb 3899 df-dif 3953 df-un 3955 df-in 3957 df-ss 3967 df-pss 3970 df-nul 4333 df-if 4525 df-pw 4601 df-sn 4626 df-pr 4628 df-op 4632 df-uni 4907 df-int 4946 df-iun 4992 df-br 5143 df-opab 5205 df-mpt 5225 df-tr 5259 df-id 5577 df-eprel 5583 df-po 5591 df-so 5592 df-fr 5636 df-se 5637 df-we 5638 df-xp 5690 df-rel 5691 df-cnv 5692 df-co 5693 df-dm 5694 df-rn 5695 df-res 5696 df-ima 5697 df-pred 6320 df-ord 6386 df-on 6387 df-lim 6388 df-suc 6389 df-iota 6513 df-fun 6562 df-fn 6563 df-f 6564 df-f1 6565 df-fo 6566 df-f1o 6567 df-fv 6568 df-isom 6569 df-riota 7389 df-ov 7435 df-oprab 7436 df-mpo 7437 df-om 7889 df-1st 8015 df-2nd 8016 df-frecs 8307 df-wrecs 8338 df-recs 8412 df-rdg 8451 df-1o 8507 df-er 8746 df-map 8869 df-en 8987 df-dom 8988 df-sdom 8989 df-fin 8990 df-oi 9551 df-card 9980 df-acn 9983 | 
| This theorem is referenced by: unictb 10616 iunctb2 37405 heiborlem3 37821 | 
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