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Theorem presucmap 38607
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 38608 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 38590 . . 3 (𝑁 ∈ ran SucMap → pre 𝑁 = (℩𝑚𝑚 SucMap 𝑁))
21eqcomd 2740 . 2 (𝑁 ∈ ran SucMap → (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁)
3 preex 38604 . . 3 pre 𝑁 ∈ V
4 eupre2 38605 . . . 4 (𝑁 ∈ ran SucMap → (𝑁 ∈ ran SucMap ↔ ∃!𝑚 𝑚 SucMap 𝑁))
54ibi 267 . . 3 (𝑁 ∈ ran SucMap → ∃!𝑚 𝑚 SucMap 𝑁)
6 breq1 5099 . . . 4 (𝑚 = pre 𝑁 → (𝑚 SucMap 𝑁 ↔ pre 𝑁 SucMap 𝑁))
76iota2 6479 . . 3 (( pre 𝑁 ∈ V ∧ ∃!𝑚 𝑚 SucMap 𝑁) → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁))
83, 5, 7sylancr 587 . 2 (𝑁 ∈ ran SucMap → ( pre 𝑁 SucMap 𝑁 ↔ (℩𝑚𝑚 SucMap 𝑁) = pre 𝑁))
92, 8mpbird 257 1 (𝑁 ∈ ran SucMap → pre 𝑁 SucMap 𝑁)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 206   = wceq 1541  wcel 2113  ∃!weu 2566  Vcvv 3438   class class class wbr 5096  ran crn 5623  cio 6444   SucMap csucmap 38317   pre cpre 38319
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-10 2146  ax-11 2162  ax-12 2182  ax-ext 2706  ax-sep 5239  ax-nul 5249  ax-pr 5375  ax-un 7678  ax-reg 9495
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-nf 1785  df-sb 2068  df-mo 2537  df-eu 2567  df-clab 2713  df-cleq 2726  df-clel 2809  df-nfc 2883  df-ne 2931  df-ral 3050  df-rex 3059  df-rab 3398  df-v 3440  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4284  df-if 4478  df-pw 4554  df-sn 4579  df-pr 4581  df-op 4585  df-uni 4862  df-br 5097  df-opab 5159  df-eprel 5522  df-fr 5575  df-xp 5628  df-cnv 5630  df-dm 5632  df-rn 5633  df-res 5634  df-ima 5635  df-pred 6257  df-suc 6321  df-iota 6446  df-sucmap 38575  df-pre 38588
This theorem is referenced by:  preuniqval  38608  sucpre  38609
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