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Theorem xpord2ind 8173
Description: Induction over the Cartesian product ordering. Note that the substitutions cover all possible cases of membership in the predecessor class. (Contributed by Scott Fenton, 22-Aug-2024.)
Hypotheses
Ref Expression
xpord2ind.1 𝑅 Fr 𝐴
xpord2ind.2 𝑅 Po 𝐴
xpord2ind.3 𝑅 Se 𝐴
xpord2ind.4 𝑆 Fr 𝐵
xpord2ind.5 𝑆 Po 𝐵
xpord2ind.6 𝑆 Se 𝐵
xpord2ind.7 (𝑎 = 𝑐 → (𝜑𝜓))
xpord2ind.8 (𝑏 = 𝑑 → (𝜓𝜒))
xpord2ind.9 (𝑎 = 𝑐 → (𝜃𝜒))
xpord2ind.11 (𝑎 = 𝑋 → (𝜑𝜏))
xpord2ind.12 (𝑏 = 𝑌 → (𝜏𝜂))
xpord2ind.i ((𝑎𝐴𝑏𝐵) → ((∀𝑐 ∈ Pred (𝑅, 𝐴, 𝑎)∀𝑑 ∈ Pred (𝑆, 𝐵, 𝑏)𝜒 ∧ ∀𝑐 ∈ Pred (𝑅, 𝐴, 𝑎)𝜓 ∧ ∀𝑑 ∈ Pred (𝑆, 𝐵, 𝑏)𝜃) → 𝜑))
Assertion
Ref Expression
xpord2ind ((𝑋𝐴𝑌𝐵) → 𝜂)
Distinct variable groups:   𝐴,𝑎,𝑏,𝑐,𝑑   𝜓,𝑎   𝜏,𝑎   𝐵,𝑎,𝑏,𝑐,𝑑   𝜒,𝑏   𝜂,𝑏   𝜑,𝑐   𝜃,𝑐   𝜓,𝑑   𝑅,𝑎,𝑏,𝑐,𝑑   𝑆,𝑎,𝑏,𝑐,𝑑   𝑋,𝑎,𝑏   𝑌,𝑏
Allowed substitution hints:   𝜑(𝑎,𝑏,𝑑)   𝜓(𝑏,𝑐)   𝜒(𝑎,𝑐,𝑑)   𝜃(𝑎,𝑏,𝑑)   𝜏(𝑏,𝑐,𝑑)   𝜂(𝑎,𝑐,𝑑)   𝑋(𝑐,𝑑)   𝑌(𝑎,𝑐,𝑑)

Proof of Theorem xpord2ind
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eqid 2737 . 2 {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵) ∧ (((1st𝑥)𝑅(1st𝑦) ∨ (1st𝑥) = (1st𝑦)) ∧ ((2nd𝑥)𝑆(2nd𝑦) ∨ (2nd𝑥) = (2nd𝑦)) ∧ 𝑥𝑦))} = {⟨𝑥, 𝑦⟩ ∣ (𝑥 ∈ (𝐴 × 𝐵) ∧ 𝑦 ∈ (𝐴 × 𝐵) ∧ (((1st𝑥)𝑅(1st𝑦) ∨ (1st𝑥) = (1st𝑦)) ∧ ((2nd𝑥)𝑆(2nd𝑦) ∨ (2nd𝑥) = (2nd𝑦)) ∧ 𝑥𝑦))}
2 xpord2ind.1 . 2 𝑅 Fr 𝐴
3 xpord2ind.2 . 2 𝑅 Po 𝐴
4 xpord2ind.3 . 2 𝑅 Se 𝐴
5 xpord2ind.4 . 2 𝑆 Fr 𝐵
6 xpord2ind.5 . 2 𝑆 Po 𝐵
7 xpord2ind.6 . 2 𝑆 Se 𝐵
8 xpord2ind.7 . 2 (𝑎 = 𝑐 → (𝜑𝜓))
9 xpord2ind.8 . 2 (𝑏 = 𝑑 → (𝜓𝜒))
10 xpord2ind.9 . 2 (𝑎 = 𝑐 → (𝜃𝜒))
11 xpord2ind.11 . 2 (𝑎 = 𝑋 → (𝜑𝜏))
12 xpord2ind.12 . 2 (𝑏 = 𝑌 → (𝜏𝜂))
13 xpord2ind.i . 2 ((𝑎𝐴𝑏𝐵) → ((∀𝑐 ∈ Pred (𝑅, 𝐴, 𝑎)∀𝑑 ∈ Pred (𝑆, 𝐵, 𝑏)𝜒 ∧ ∀𝑐 ∈ Pred (𝑅, 𝐴, 𝑎)𝜓 ∧ ∀𝑑 ∈ Pred (𝑆, 𝐵, 𝑏)𝜃) → 𝜑))
141, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13xpord2indlem 8172 1 ((𝑋𝐴𝑌𝐵) → 𝜂)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 206  wa 395  wo 848  w3a 1087   = wceq 1540  wcel 2108  wne 2940  wral 3061   class class class wbr 5143  {copab 5205   Po wpo 5590   Fr wfr 5634   Se wse 5635   × cxp 5683  Predcpred 6320  cfv 6561  1st c1st 8012  2nd c2nd 8013
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-10 2141  ax-11 2157  ax-12 2177  ax-ext 2708  ax-sep 5296  ax-nul 5306  ax-pow 5365  ax-pr 5432  ax-un 7755
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2065  df-mo 2540  df-eu 2569  df-clab 2715  df-cleq 2729  df-clel 2816  df-nfc 2892  df-ne 2941  df-ral 3062  df-rex 3071  df-rab 3437  df-v 3482  df-sbc 3789  df-csb 3900  df-dif 3954  df-un 3956  df-in 3958  df-ss 3968  df-nul 4334  df-if 4526  df-pw 4602  df-sn 4627  df-pr 4629  df-op 4633  df-uni 4908  df-iun 4993  df-br 5144  df-opab 5206  df-mpt 5226  df-id 5578  df-po 5592  df-fr 5637  df-se 5638  df-xp 5691  df-rel 5692  df-cnv 5693  df-co 5694  df-dm 5695  df-rn 5696  df-res 5697  df-ima 5698  df-pred 6321  df-iota 6514  df-fun 6563  df-fv 6569  df-1st 8014  df-2nd 8015
This theorem is referenced by:  on2ind  8707  no2indslem  27987
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