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Mathbox for Emmett Weisz |
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Mirrors > Home > MPE Home > Th. List > Mathboxes > 0setrec | Structured version Visualization version GIF version |
Description: If a function sends the empty set to itself, the function will not recursively generate any sets, regardless of its other values. (Contributed by Emmett Weisz, 23-Jun-2021.) |
Ref | Expression |
---|---|
0setrec.1 | ⊢ (𝜑 → (𝐹‘∅) = ∅) |
Ref | Expression |
---|---|
0setrec | ⊢ (𝜑 → setrecs(𝐹) = ∅) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eqid 2735 | . . 3 ⊢ setrecs(𝐹) = setrecs(𝐹) | |
2 | ss0 4408 | . . . . 5 ⊢ (𝑥 ⊆ ∅ → 𝑥 = ∅) | |
3 | fveq2 6907 | . . . . . . 7 ⊢ (𝑥 = ∅ → (𝐹‘𝑥) = (𝐹‘∅)) | |
4 | 0setrec.1 | . . . . . . 7 ⊢ (𝜑 → (𝐹‘∅) = ∅) | |
5 | 3, 4 | sylan9eqr 2797 | . . . . . 6 ⊢ ((𝜑 ∧ 𝑥 = ∅) → (𝐹‘𝑥) = ∅) |
6 | 5 | ex 412 | . . . . 5 ⊢ (𝜑 → (𝑥 = ∅ → (𝐹‘𝑥) = ∅)) |
7 | eqimss 4054 | . . . . 5 ⊢ ((𝐹‘𝑥) = ∅ → (𝐹‘𝑥) ⊆ ∅) | |
8 | 2, 6, 7 | syl56 36 | . . . 4 ⊢ (𝜑 → (𝑥 ⊆ ∅ → (𝐹‘𝑥) ⊆ ∅)) |
9 | 8 | alrimiv 1925 | . . 3 ⊢ (𝜑 → ∀𝑥(𝑥 ⊆ ∅ → (𝐹‘𝑥) ⊆ ∅)) |
10 | 1, 9 | setrec2v 48927 | . 2 ⊢ (𝜑 → setrecs(𝐹) ⊆ ∅) |
11 | ss0 4408 | . 2 ⊢ (setrecs(𝐹) ⊆ ∅ → setrecs(𝐹) = ∅) | |
12 | 10, 11 | syl 17 | 1 ⊢ (𝜑 → setrecs(𝐹) = ∅) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 = wceq 1537 ⊆ wss 3963 ∅c0 4339 ‘cfv 6563 setrecscsetrecs 48914 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1792 ax-4 1806 ax-5 1908 ax-6 1965 ax-7 2005 ax-8 2108 ax-9 2116 ax-10 2139 ax-11 2155 ax-12 2175 ax-ext 2706 ax-rep 5285 ax-sep 5302 ax-nul 5312 ax-pow 5371 ax-pr 5438 ax-un 7754 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3an 1088 df-tru 1540 df-fal 1550 df-ex 1777 df-nf 1781 df-sb 2063 df-mo 2538 df-eu 2567 df-clab 2713 df-cleq 2727 df-clel 2814 df-nfc 2890 df-ne 2939 df-ral 3060 df-rex 3069 df-rab 3434 df-v 3480 df-dif 3966 df-un 3968 df-in 3970 df-ss 3980 df-nul 4340 df-if 4532 df-pw 4607 df-sn 4632 df-pr 4634 df-op 4638 df-uni 4913 df-br 5149 df-opab 5211 df-id 5583 df-xp 5695 df-rel 5696 df-cnv 5697 df-co 5698 df-dm 5699 df-rn 5700 df-res 5701 df-ima 5702 df-iota 6516 df-fun 6565 df-fv 6571 df-setrecs 48915 |
This theorem is referenced by: (None) |
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