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Mirrors > Home > MPE Home > Th. List > ensn1OLD | Structured version Visualization version GIF version |
Description: Obsolete version of ensn1 9019 as of 23-Sep-2024. (Contributed by NM, 4-Nov-2002.) (Proof modification is discouraged.) (New usage is discouraged.) |
Ref | Expression |
---|---|
ensn1OLD.1 | ⊢ 𝐴 ∈ V |
Ref | Expression |
---|---|
ensn1OLD | ⊢ {𝐴} ≈ 1o |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | snex 5424 | . . . 4 ⊢ {⟨𝐴, ∅⟩} ∈ V | |
2 | f1oeq1 6815 | . . . 4 ⊢ (𝑓 = {⟨𝐴, ∅⟩} → (𝑓:{𝐴}–1-1-onto→{∅} ↔ {⟨𝐴, ∅⟩}:{𝐴}–1-1-onto→{∅})) | |
3 | ensn1OLD.1 | . . . . 5 ⊢ 𝐴 ∈ V | |
4 | 0ex 5300 | . . . . 5 ⊢ ∅ ∈ V | |
5 | 3, 4 | f1osn 6867 | . . . 4 ⊢ {⟨𝐴, ∅⟩}:{𝐴}–1-1-onto→{∅} |
6 | 1, 2, 5 | ceqsexv2d 3523 | . . 3 ⊢ ∃𝑓 𝑓:{𝐴}–1-1-onto→{∅} |
7 | bren 8951 | . . 3 ⊢ ({𝐴} ≈ {∅} ↔ ∃𝑓 𝑓:{𝐴}–1-1-onto→{∅}) | |
8 | 6, 7 | mpbir 230 | . 2 ⊢ {𝐴} ≈ {∅} |
9 | df1o2 8474 | . 2 ⊢ 1o = {∅} | |
10 | 8, 9 | breqtrri 5168 | 1 ⊢ {𝐴} ≈ 1o |
Colors of variables: wff setvar class |
Syntax hints: ∃wex 1773 ∈ wcel 2098 Vcvv 3468 ∅c0 4317 {csn 4623 ⟨cop 4629 class class class wbr 5141 –1-1-onto→wf1o 6536 1oc1o 8460 ≈ cen 8938 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1789 ax-4 1803 ax-5 1905 ax-6 1963 ax-7 2003 ax-8 2100 ax-9 2108 ax-ext 2697 ax-sep 5292 ax-nul 5299 ax-pr 5420 ax-un 7722 |
This theorem depends on definitions: df-bi 206 df-an 396 df-or 845 df-3an 1086 df-tru 1536 df-fal 1546 df-ex 1774 df-sb 2060 df-mo 2528 df-clab 2704 df-cleq 2718 df-clel 2804 df-ral 3056 df-rex 3065 df-rab 3427 df-v 3470 df-dif 3946 df-un 3948 df-in 3950 df-ss 3960 df-nul 4318 df-if 4524 df-sn 4624 df-pr 4626 df-op 4630 df-uni 4903 df-br 5142 df-opab 5204 df-id 5567 df-xp 5675 df-rel 5676 df-cnv 5677 df-co 5678 df-dm 5679 df-rn 5680 df-suc 6364 df-fun 6539 df-fn 6540 df-f 6541 df-f1 6542 df-fo 6543 df-f1o 6544 df-1o 8467 df-en 8942 |
This theorem is referenced by: (None) |
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