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Theorem presucmap 38994
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 38995 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 38976 . . 3 (𝑁 ∈ ran SucMap → pre 𝑁 = (℩𝑚𝑚 SucMap 𝑁))
21eqcomd 2768 . 2 (𝑁 ∈ ran SucMap → (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁)
3 preex 38991 . . 3 pre 𝑁 ∈ V
4 eupre2 38992 . . . 4 (𝑁 ∈ ran SucMap → (𝑁 ∈ ran SucMap ↔ ∃!𝑚 𝑚 SucMap 𝑁))
54ibi 269 . . 3 (𝑁 ∈ ran SucMap → ∃!𝑚 𝑚 SucMap 𝑁)
6 breq1 5103 . . . 4 (𝑚 = pre 𝑁 → (𝑚 SucMap 𝑁 ↔ pre 𝑁 SucMap 𝑁))
76iota2 6510 . . 3 (( pre 𝑁 ∈ V ∧ ∃!𝑚 𝑚 SucMap 𝑁) → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁))
83, 5, 7sylancr 596 . 2 (𝑁 ∈ ran SucMap → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁))
92, 8mpbird 259 1 (𝑁 ∈ ran SucMap → pre 𝑁 SucMap 𝑁)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 208   = wceq 1560  wcel 2142  ∃!weu 2595  Vcvv 3454   class class class wbr 5100  ran crn 5648  cio 6475   SucMap csucmap 38677   pre cpre 38679
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1815  ax-4 1829  ax-5 1930  ax-6 1987  ax-7 2028  ax-8 2144  ax-9 2152  ax-10 2175  ax-11 2191  ax-12 2212  ax-ext 2734  ax-sep 5246  ax-nul 5256  ax-pr 5390  ax-un 7718  ax-reg 9540
This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1100  df-tru 1563  df-fal 1573  df-ex 1800  df-nf 1804  df-sb 2091  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3077  df-rex 3087  df-rab 3415  df-v 3456  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-nul 4286  df-if 4481  df-pw 4557  df-sn 4583  df-pr 4585  df-op 4589  df-uni 4866  df-br 5101  df-opab 5163  df-eprel 5547  df-fr 5600  df-xp 5653  df-cnv 5655  df-dm 5657  df-rn 5658  df-res 5659  df-ima 5660  df-pred 6288  df-suc 6352  df-iota 6477  df-sucmap 38961  df-pre 38974
This theorem is referenced by:  preuniqval  38995  sucpre  38996
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