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Theorem presuc 39696
Description: pre is a left-inverse of suc. This theorem gives a clean rewrite rule that eliminates pre on explicit successors. (Contributed by Peter Mazsa, 12-Jan-2026.)
Assertion
Ref Expression
presuc (𝑀 ∈ 𝑉 → pre suc 𝑀 = 𝑀)

Proof of Theorem presuc
StepHypRef Expression
1 sucmapsuc 39687 . . 3 (𝑀 ∈ 𝑉 → 𝑀 SucMap suc 𝑀)
2 relsucmap 39665 . . . . 5 Rel SucMap
32relelrni 5943 . . . 4 (𝑀 SucMap suc 𝑀 → suc 𝑀 ∈ ran SucMap )
4 df-succl 39667 . . . 4 Suc = ran SucMap
53, 4eleqtrrdi 2875 . . 3 (𝑀 SucMap suc 𝑀 → suc 𝑀 ∈ Suc )
6 sucpre 39695 . . 3 (suc 𝑀 ∈ Suc → suc pre suc 𝑀 = suc 𝑀)
71, 5, 63syl 19 . 2 (𝑀 ∈ 𝑉 → suc pre suc 𝑀 = suc 𝑀)
8 suc11reg 9657 . 2 (suc pre suc 𝑀 = suc 𝑀 ↔ pre suc 𝑀 = 𝑀)
97, 8sylib 221 1 (𝑀 ∈ 𝑉 → pre suc 𝑀 = 𝑀)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4   = wceq 1570   ∈ wcel 2147   class class class wbr 5108  ran crn 5659  suc csuc 6390   SucMap csucmap 39376   Suc csuccl 39377   pre cpre 39378
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 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735  ax-sep 5255  ax-nul 5266  ax-pr 5398  ax-un 7783  ax-reg 9623
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 2102  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3081  df-rex 3091  df-rab 3417  df-v 3456  df-ss 3901  df-dif 4050  df-in 4094  df-un 4154  df-nul 4282  df-if 4486  df-pw 4562  df-sn 4589  df-pr 4591  df-op 4841  df-uni 4873  df-br 5109  df-opab 5174  df-eprel 5558  df-fr 5611  df-xp 5664  df-rel 5665  df-cnv 5666  df-dm 5668  df-rn 5669  df-res 5670  df-ima 5671  df-pred 6330  df-suc 6394  df-iota 6520  df-sucmap 39660  df-succl 39667  df-pre 39673
This theorem is used by: (None)
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