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Theorem presucmap 39246
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 39247 gives it is the only one. (Contributed by Peter Mazsa, 12-Jan-2026.)
Assertion
Ref Expression
presucmap (𝑁 ∈ ran SucMap → pre 𝑁 SucMap 𝑁)

Proof of Theorem presucmap
Dummy variable 𝑚 is distinct from all other variables.
StepHypRef Expression
1 dfpre2 39228 . . 3 (𝑁 ∈ ran SucMap → pre 𝑁 = (℩𝑚𝑚 SucMap 𝑁))
21eqcomd 2766 . 2 (𝑁 ∈ ran SucMap → (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁)
3 preex 39243 . . 3 pre 𝑁 ∈ V
4 eupre2 39244 . . . 4 (𝑁 ∈ ran SucMap → (𝑁 ∈ ran SucMap ↔ ∃!𝑚 𝑚 SucMap 𝑁))
54ibi 270 . . 3 (𝑁 ∈ ran SucMap → ∃!𝑚 𝑚 SucMap 𝑁)
6 breq1 5106 . . . 4 (𝑚 = pre 𝑁 → (𝑚 SucMap 𝑁 ↔ pre 𝑁 SucMap 𝑁))
76iota2 6522 . . 3 (( pre 𝑁 ∈ V ∧ ∃!𝑚 𝑚 SucMap 𝑁) → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁))
83, 5, 7sylancr 599 . 2 (𝑁 ∈ ran SucMap → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁))
92, 8mpbird 260 1 (𝑁 ∈ ran SucMap → pre 𝑁 SucMap 𝑁)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  wi 4  wb 209   = wceq 1570  wcel 2145  ∃!weu 2593  Vcvv 3450   class class class wbr 5103  ran crn 5656  cio 6487   SucMap csucmap 38929   pre cpre 38931
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2213  ax-ext 2732  ax-sep 5251  ax-nul 5263  ax-pr 5398  ax-un 7737  ax-reg 9567
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-ral 3077  df-rex 3087  df-rab 3413  df-v 3452  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-br 5104  df-opab 5168  df-eprel 5555  df-fr 5608  df-xp 5661  df-cnv 5663  df-dm 5665  df-rn 5666  df-res 5667  df-ima 5668  df-pred 6299  df-suc 6363  df-iota 6489  df-sucmap 39213  df-pre 39226
This theorem is used by:  preuniqval  39247  sucpre  39248
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