Description: Induction over the triple Cartesian product ordering. Note that the substitutions cover all possible cases of membership in the predecessor class. (Contributed by Scott Fenton, 2-Feb-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | xpord3indd.x | ⊢ ( 𝜅 → 𝑋 ∈ 𝐴 ) | |
| xpord3indd.y | ⊢ ( 𝜅 → 𝑌 ∈ 𝐵 ) | ||
| xpord3indd.z | ⊢ ( 𝜅 → 𝑍 ∈ 𝐶 ) | ||
| xpord3indd.1 | ⊢ ( 𝜅 → 𝑅 Fr 𝐴 ) | ||
| xpord3indd.2 | ⊢ ( 𝜅 → 𝑅 Po 𝐴 ) | ||
| xpord3indd.3 | ⊢ ( 𝜅 → 𝑅 Se 𝐴 ) | ||
| xpord3indd.4 | ⊢ ( 𝜅 → 𝑆 Fr 𝐵 ) | ||
| xpord3indd.5 | ⊢ ( 𝜅 → 𝑆 Po 𝐵 ) | ||
| xpord3indd.6 | ⊢ ( 𝜅 → 𝑆 Se 𝐵 ) | ||
| xpord3indd.7 | ⊢ ( 𝜅 → 𝑇 Fr 𝐶 ) | ||
| xpord3indd.8 | ⊢ ( 𝜅 → 𝑇 Po 𝐶 ) | ||
| xpord3indd.9 | ⊢ ( 𝜅 → 𝑇 Se 𝐶 ) | ||
| xpord3indd.10 | ⊢ ( 𝑎 = 𝑑 → ( 𝜑 ↔ 𝜓 ) ) | ||
| xpord3indd.11 | ⊢ ( 𝑏 = 𝑒 → ( 𝜓 ↔ 𝜒 ) ) | ||
| xpord3indd.12 | ⊢ ( 𝑐 = 𝑓 → ( 𝜒 ↔ 𝜃 ) ) | ||
| xpord3indd.13 | ⊢ ( 𝑎 = 𝑑 → ( 𝜏 ↔ 𝜃 ) ) | ||
| xpord3indd.14 | ⊢ ( 𝑏 = 𝑒 → ( 𝜂 ↔ 𝜏 ) ) | ||
| xpord3indd.15 | ⊢ ( 𝑏 = 𝑒 → ( 𝜁 ↔ 𝜃 ) ) | ||
| xpord3indd.16 | ⊢ ( 𝑐 = 𝑓 → ( 𝜎 ↔ 𝜏 ) ) | ||
| xpord3indd.17 | ⊢ ( 𝑎 = 𝑋 → ( 𝜑 ↔ 𝜌 ) ) | ||
| xpord3indd.18 | ⊢ ( 𝑏 = 𝑌 → ( 𝜌 ↔ 𝜇 ) ) | ||
| xpord3indd.19 | ⊢ ( 𝑐 = 𝑍 → ( 𝜇 ↔ 𝜆 ) ) | ||
| xpord3indd.i | ⊢ ( ( 𝜅 ∧ ( 𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵 ∧ 𝑐 ∈ 𝐶 ) ) → ( ( ( ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜃 ∧ ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) 𝜒 ∧ ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜁 ) ∧ ( ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) 𝜓 ∧ ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜏 ∧ ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) 𝜎 ) ∧ ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜂 ) → 𝜑 ) ) | ||
| Assertion | xpord3indd | ⊢ ( 𝜅 → 𝜆 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | xpord3indd.x | ⊢ ( 𝜅 → 𝑋 ∈ 𝐴 ) | |
| 2 | xpord3indd.y | ⊢ ( 𝜅 → 𝑌 ∈ 𝐵 ) | |
| 3 | xpord3indd.z | ⊢ ( 𝜅 → 𝑍 ∈ 𝐶 ) | |
| 4 | xpord3indd.1 | ⊢ ( 𝜅 → 𝑅 Fr 𝐴 ) | |
| 5 | xpord3indd.2 | ⊢ ( 𝜅 → 𝑅 Po 𝐴 ) | |
| 6 | xpord3indd.3 | ⊢ ( 𝜅 → 𝑅 Se 𝐴 ) | |
| 7 | xpord3indd.4 | ⊢ ( 𝜅 → 𝑆 Fr 𝐵 ) | |
| 8 | xpord3indd.5 | ⊢ ( 𝜅 → 𝑆 Po 𝐵 ) | |
| 9 | xpord3indd.6 | ⊢ ( 𝜅 → 𝑆 Se 𝐵 ) | |
| 10 | xpord3indd.7 | ⊢ ( 𝜅 → 𝑇 Fr 𝐶 ) | |
| 11 | xpord3indd.8 | ⊢ ( 𝜅 → 𝑇 Po 𝐶 ) | |
| 12 | xpord3indd.9 | ⊢ ( 𝜅 → 𝑇 Se 𝐶 ) | |
| 13 | xpord3indd.10 | ⊢ ( 𝑎 = 𝑑 → ( 𝜑 ↔ 𝜓 ) ) | |
| 14 | xpord3indd.11 | ⊢ ( 𝑏 = 𝑒 → ( 𝜓 ↔ 𝜒 ) ) | |
| 15 | xpord3indd.12 | ⊢ ( 𝑐 = 𝑓 → ( 𝜒 ↔ 𝜃 ) ) | |
| 16 | xpord3indd.13 | ⊢ ( 𝑎 = 𝑑 → ( 𝜏 ↔ 𝜃 ) ) | |
| 17 | xpord3indd.14 | ⊢ ( 𝑏 = 𝑒 → ( 𝜂 ↔ 𝜏 ) ) | |
| 18 | xpord3indd.15 | ⊢ ( 𝑏 = 𝑒 → ( 𝜁 ↔ 𝜃 ) ) | |
| 19 | xpord3indd.16 | ⊢ ( 𝑐 = 𝑓 → ( 𝜎 ↔ 𝜏 ) ) | |
| 20 | xpord3indd.17 | ⊢ ( 𝑎 = 𝑋 → ( 𝜑 ↔ 𝜌 ) ) | |
| 21 | xpord3indd.18 | ⊢ ( 𝑏 = 𝑌 → ( 𝜌 ↔ 𝜇 ) ) | |
| 22 | xpord3indd.19 | ⊢ ( 𝑐 = 𝑍 → ( 𝜇 ↔ 𝜆 ) ) | |
| 23 | xpord3indd.i | ⊢ ( ( 𝜅 ∧ ( 𝑎 ∈ 𝐴 ∧ 𝑏 ∈ 𝐵 ∧ 𝑐 ∈ 𝐶 ) ) → ( ( ( ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜃 ∧ ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) 𝜒 ∧ ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜁 ) ∧ ( ∀ 𝑑 ∈ Pred ( 𝑅 , 𝐴 , 𝑎 ) 𝜓 ∧ ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜏 ∧ ∀ 𝑒 ∈ Pred ( 𝑆 , 𝐵 , 𝑏 ) 𝜎 ) ∧ ∀ 𝑓 ∈ Pred ( 𝑇 , 𝐶 , 𝑐 ) 𝜂 ) → 𝜑 ) ) | |
| 24 | eqid | ⊢ { 〈 𝑥 , 𝑦 〉 ∣ ( 𝑥 ∈ ( ( 𝐴 × 𝐵 ) × 𝐶 ) ∧ 𝑦 ∈ ( ( 𝐴 × 𝐵 ) × 𝐶 ) ∧ ( ( ( ( 1st ‘ ( 1st ‘ 𝑥 ) ) 𝑅 ( 1st ‘ ( 1st ‘ 𝑦 ) ) ∨ ( 1st ‘ ( 1st ‘ 𝑥 ) ) = ( 1st ‘ ( 1st ‘ 𝑦 ) ) ) ∧ ( ( 2nd ‘ ( 1st ‘ 𝑥 ) ) 𝑆 ( 2nd ‘ ( 1st ‘ 𝑦 ) ) ∨ ( 2nd ‘ ( 1st ‘ 𝑥 ) ) = ( 2nd ‘ ( 1st ‘ 𝑦 ) ) ) ∧ ( ( 2nd ‘ 𝑥 ) 𝑇 ( 2nd ‘ 𝑦 ) ∨ ( 2nd ‘ 𝑥 ) = ( 2nd ‘ 𝑦 ) ) ) ∧ 𝑥 ≠ 𝑦 ) ) } = { 〈 𝑥 , 𝑦 〉 ∣ ( 𝑥 ∈ ( ( 𝐴 × 𝐵 ) × 𝐶 ) ∧ 𝑦 ∈ ( ( 𝐴 × 𝐵 ) × 𝐶 ) ∧ ( ( ( ( 1st ‘ ( 1st ‘ 𝑥 ) ) 𝑅 ( 1st ‘ ( 1st ‘ 𝑦 ) ) ∨ ( 1st ‘ ( 1st ‘ 𝑥 ) ) = ( 1st ‘ ( 1st ‘ 𝑦 ) ) ) ∧ ( ( 2nd ‘ ( 1st ‘ 𝑥 ) ) 𝑆 ( 2nd ‘ ( 1st ‘ 𝑦 ) ) ∨ ( 2nd ‘ ( 1st ‘ 𝑥 ) ) = ( 2nd ‘ ( 1st ‘ 𝑦 ) ) ) ∧ ( ( 2nd ‘ 𝑥 ) 𝑇 ( 2nd ‘ 𝑦 ) ∨ ( 2nd ‘ 𝑥 ) = ( 2nd ‘ 𝑦 ) ) ) ∧ 𝑥 ≠ 𝑦 ) ) } | |
| 25 | 24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | xpord3inddlem | ⊢ ( 𝜅 → 𝜆 ) |