| Mathbox for Peter Mazsa |
< Previous
Next >
Nearby theorems |
||
| Mirrors > Home > MPE Home > Th. List > Mathboxes > presucmap | Structured version Visualization version GIF version | ||
| Description: pre is really a predecessor (when it should be). This correctness theorem for pre makes it usable in proofs without unfolding ℩. This theorem gives one witness; preuniqval 38834 gives it is the only one. (Contributed by Peter Mazsa, 12-Jan-2026.) |
| Ref | Expression |
|---|---|
| presucmap | ⊢ (𝑁 ∈ ran SucMap → pre 𝑁 SucMap 𝑁) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | dfpre2 38815 | . . 3 ⊢ (𝑁 ∈ ran SucMap → pre 𝑁 = (℩𝑚𝑚 SucMap 𝑁)) | |
| 2 | 1 | eqcomd 2743 | . 2 ⊢ (𝑁 ∈ ran SucMap → (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁) |
| 3 | preex 38830 | . . 3 ⊢ pre 𝑁 ∈ V | |
| 4 | eupre2 38831 | . . . 4 ⊢ (𝑁 ∈ ran SucMap → (𝑁 ∈ ran SucMap ↔ ∃!𝑚 𝑚 SucMap 𝑁)) | |
| 5 | 4 | ibi 267 | . . 3 ⊢ (𝑁 ∈ ran SucMap → ∃!𝑚 𝑚 SucMap 𝑁) |
| 6 | breq1 5089 | . . . 4 ⊢ (𝑚 = pre 𝑁 → (𝑚 SucMap 𝑁 ↔ pre 𝑁 SucMap 𝑁)) | |
| 7 | 6 | iota2 6482 | . . 3 ⊢ (( pre 𝑁 ∈ V ∧ ∃!𝑚 𝑚 SucMap 𝑁) → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁)) |
| 8 | 3, 5, 7 | sylancr 588 | . 2 ⊢ (𝑁 ∈ ran SucMap → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁)) |
| 9 | 2, 8 | mpbird 257 | 1 ⊢ (𝑁 ∈ ran SucMap → pre 𝑁 SucMap 𝑁) |
| Colors of variables: wff setvar class |
| Syntax hints: → wi 4 ↔ wb 206 = wceq 1542 ∈ wcel 2114 ∃!weu 2569 Vcvv 3430 class class class wbr 5086 ran crn 5626 ℩cio 6447 SucMap csucmap 38516 pre cpre 38518 |
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1797 ax-4 1811 ax-5 1912 ax-6 1969 ax-7 2010 ax-8 2116 ax-9 2124 ax-10 2147 ax-11 2163 ax-12 2185 ax-ext 2709 ax-sep 5232 ax-nul 5242 ax-pr 5371 ax-un 7683 ax-reg 9501 |
| This theorem depends on definitions: df-bi 207 df-an 396 df-or 849 df-3an 1089 df-tru 1545 df-fal 1555 df-ex 1782 df-nf 1786 df-sb 2069 df-mo 2540 df-eu 2570 df-clab 2716 df-cleq 2729 df-clel 2812 df-nfc 2886 df-ne 2934 df-ral 3053 df-rex 3063 df-rab 3391 df-v 3432 df-dif 3893 df-un 3895 df-in 3897 df-ss 3907 df-nul 4275 df-if 4468 df-pw 4544 df-sn 4569 df-pr 4571 df-op 4575 df-uni 4852 df-br 5087 df-opab 5149 df-eprel 5525 df-fr 5578 df-xp 5631 df-cnv 5633 df-dm 5635 df-rn 5636 df-res 5637 df-ima 5638 df-pred 6260 df-suc 6324 df-iota 6449 df-sucmap 38800 df-pre 38813 |
| This theorem is referenced by: preuniqval 38834 sucpre 38835 |
| Copyright terms: Public domain | W3C validator |