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Mirrors > Home > MPE Home > Th. List > bren | Structured version Visualization version GIF version |
Description: Equinumerosity relation. (Contributed by NM, 15-Jun-1998.) Extract breng 8992 as an intermediate result. (Revised by BTernaryTau, 23-Sep-2024.) |
Ref | Expression |
---|---|
bren | ⊢ (𝐴 ≈ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | encv 8991 | . 2 ⊢ (𝐴 ≈ 𝐵 → (𝐴 ∈ V ∧ 𝐵 ∈ V)) | |
2 | f1ofn 6849 | . . . . 5 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝑓 Fn 𝐴) | |
3 | fndm 6671 | . . . . . 6 ⊢ (𝑓 Fn 𝐴 → dom 𝑓 = 𝐴) | |
4 | vex 3481 | . . . . . . 7 ⊢ 𝑓 ∈ V | |
5 | 4 | dmex 7931 | . . . . . 6 ⊢ dom 𝑓 ∈ V |
6 | 3, 5 | eqeltrrdi 2847 | . . . . 5 ⊢ (𝑓 Fn 𝐴 → 𝐴 ∈ V) |
7 | 2, 6 | syl 17 | . . . 4 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝐴 ∈ V) |
8 | f1ofo 6855 | . . . . . 6 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝑓:𝐴–onto→𝐵) | |
9 | forn 6823 | . . . . . 6 ⊢ (𝑓:𝐴–onto→𝐵 → ran 𝑓 = 𝐵) | |
10 | 8, 9 | syl 17 | . . . . 5 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → ran 𝑓 = 𝐵) |
11 | 4 | rnex 7932 | . . . . 5 ⊢ ran 𝑓 ∈ V |
12 | 10, 11 | eqeltrrdi 2847 | . . . 4 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝐵 ∈ V) |
13 | 7, 12 | jca 511 | . . 3 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → (𝐴 ∈ V ∧ 𝐵 ∈ V)) |
14 | 13 | exlimiv 1927 | . 2 ⊢ (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (𝐴 ∈ V ∧ 𝐵 ∈ V)) |
15 | breng 8992 | . 2 ⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴 ≈ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵)) | |
16 | 1, 14, 15 | pm5.21nii 378 | 1 ⊢ (𝐴 ≈ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵) |
Colors of variables: wff setvar class |
Syntax hints: ↔ wb 206 ∧ wa 395 = wceq 1536 ∃wex 1775 ∈ wcel 2105 Vcvv 3477 class class class wbr 5147 dom cdm 5688 ran crn 5689 Fn wfn 6557 –onto→wfo 6560 –1-1-onto→wf1o 6561 ≈ cen 8980 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1791 ax-4 1805 ax-5 1907 ax-6 1964 ax-7 2004 ax-8 2107 ax-9 2115 ax-ext 2705 ax-sep 5301 ax-nul 5311 ax-pr 5437 ax-un 7753 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3an 1088 df-tru 1539 df-fal 1549 df-ex 1776 df-sb 2062 df-clab 2712 df-cleq 2726 df-clel 2813 df-ral 3059 df-rex 3068 df-rab 3433 df-v 3479 df-dif 3965 df-un 3967 df-in 3969 df-ss 3979 df-nul 4339 df-if 4531 df-sn 4631 df-pr 4633 df-op 4637 df-uni 4912 df-br 5148 df-opab 5210 df-xp 5694 df-rel 5695 df-cnv 5696 df-dm 5698 df-rn 5699 df-fn 6565 df-f 6566 df-f1 6567 df-fo 6568 df-f1o 6569 df-en 8984 |
This theorem is referenced by: domen 9000 f1oen3g 9005 ener 9039 en0ALT 9057 unen 9084 enfixsn 9119 canth2 9168 mapen 9179 ssenen 9189 rexdif1enOLD 9197 dif1en 9198 dif1enOLD 9200 ssfiALT 9212 ensymfib 9221 entrfil 9222 phplem2 9242 php3 9246 phplem4OLD 9254 php3OLD 9258 isinf 9293 isinfOLD 9294 domunfican 9358 fiint 9363 fiintOLD 9364 mapfien2 9446 unxpwdom2 9625 isinffi 10029 infxpenc2 10059 fseqen 10064 dfac8b 10068 infpwfien 10099 dfac12r 10184 infmap2 10254 cff1 10295 infpssr 10345 fin4en1 10346 enfin2i 10358 enfin1ai 10421 axcc3 10475 axcclem 10494 numth 10509 ttukey2g 10553 canthnum 10686 canthwe 10688 canthp1 10691 pwfseq 10701 tskuni 10820 gruen 10849 hasheqf1o 14384 hashfacen 14489 fz1f1o 15742 ruc 16275 cnso 16279 eulerth 16816 ablfaclem3 20121 lbslcic 21878 uvcendim 21884 indishmph 23821 ufldom 23985 ovolctb 25538 ovoliunlem3 25552 iunmbl2 25605 dyadmbl 25648 vitali 25661 cusgrfilem3 29489 padct 32736 f1ocnt 32809 volmeas 34211 eulerpart 34363 derangenlem 35155 mblfinlem1 37643 sticksstones4 42130 sticksstones20 42147 eldioph2lem1 42747 isnumbasgrplem1 43089 nnf1oxpnn 45137 sprsymrelen 47424 prproropen 47432 uspgrspren 47995 uspgrbisymrel 47997 1aryenef 48494 2aryenef 48505 rrx2xpreen 48568 |
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