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Description: An ordered pair theorem for finite integers. Analogous to nn0opthi . (Contributed by Scott Fenton, 1-May-2012)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | omopth | ⊢ ( ( ( 𝐴 ∈ ω ∧ 𝐵 ∈ ω ) ∧ ( 𝐶 ∈ ω ∧ 𝐷 ∈ ω ) ) → ( ( ( ( 𝐴 +o 𝐵 ) ·o ( 𝐴 +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | oveq1 | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( 𝐴 +o 𝐵 ) = ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) | |
| 2 | 1 1 | oveq12d | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( ( 𝐴 +o 𝐵 ) ·o ( 𝐴 +o 𝐵 ) ) = ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) ) |
| 3 | 2 | oveq1d | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( ( ( 𝐴 +o 𝐵 ) ·o ( 𝐴 +o 𝐵 ) ) +o 𝐵 ) = ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) +o 𝐵 ) ) |
| 4 | 3 | eqeq1d | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( ( ( ( 𝐴 +o 𝐵 ) ·o ( 𝐴 +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ) ) |
| 5 | eqeq1 | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( 𝐴 = 𝐶 ↔ if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ) ) | |
| 6 | 5 | anbi1d | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |
| 7 | 4 6 | bibi12d | ⊢ ( 𝐴 = if ( 𝐴 ∈ ω , 𝐴 , ∅ ) → ( ( ( ( ( 𝐴 +o 𝐵 ) ·o ( 𝐴 +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ↔ ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) ) |
| 8 | oveq2 | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) = ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) | |
| 9 | 8 8 | oveq12d | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) = ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) ) |
| 10 | id | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) | |
| 11 | 9 10 | oveq12d | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) +o 𝐵 ) = ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) |
| 12 | 11 | eqeq1d | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ) ) |
| 13 | eqeq1 | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( 𝐵 = 𝐷 ↔ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) | |
| 14 | 13 | anbi2d | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ 𝐵 = 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) ) |
| 15 | 12 14 | bibi12d | ⊢ ( 𝐵 = if ( 𝐵 ∈ ω , 𝐵 , ∅ ) → ( ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ 𝐵 = 𝐷 ) ) ↔ ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) ) ) |
| 16 | oveq1 | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( 𝐶 +o 𝐷 ) = ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) | |
| 17 | 16 16 | oveq12d | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) = ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) ) |
| 18 | 17 | oveq1d | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) +o 𝐷 ) ) |
| 19 | 18 | eqeq2d | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) +o 𝐷 ) ) ) |
| 20 | eqeq2 | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ↔ if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ) ) | |
| 21 | 20 | anbi1d | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) ) |
| 22 | 19 21 | bibi12d | ⊢ ( 𝐶 = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) → ( ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = 𝐶 ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) ↔ ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) +o 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) ) ) |
| 23 | oveq2 | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) = ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) | |
| 24 | 23 23 | oveq12d | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) = ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) ) |
| 25 | id | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) | |
| 26 | 24 25 | oveq12d | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) +o 𝐷 ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) |
| 27 | 26 | eqeq2d | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) +o 𝐷 ) ↔ ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) ) |
| 28 | eqeq2 | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ↔ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) | |
| 29 | 28 | anbi2d | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) ) |
| 30 | 27 29 | bibi12d | ⊢ ( 𝐷 = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) → ( ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o 𝐷 ) ) +o 𝐷 ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = 𝐷 ) ) ↔ ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) ) ) |
| 31 | peano1 | ⊢ ∅ ∈ ω | |
| 32 | 31 | elimel | ⊢ if ( 𝐴 ∈ ω , 𝐴 , ∅ ) ∈ ω |
| 33 | 31 | elimel | ⊢ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ∈ ω |
| 34 | 31 | elimel | ⊢ if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∈ ω |
| 35 | 31 | elimel | ⊢ if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ∈ ω |
| 36 | 32 33 34 35 | omopthi | ⊢ ( ( ( ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ·o ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) ) +o if ( 𝐵 ∈ ω , 𝐵 , ∅ ) ) = ( ( ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ·o ( if ( 𝐶 ∈ ω , 𝐶 , ∅ ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) +o if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ↔ ( if ( 𝐴 ∈ ω , 𝐴 , ∅ ) = if ( 𝐶 ∈ ω , 𝐶 , ∅ ) ∧ if ( 𝐵 ∈ ω , 𝐵 , ∅ ) = if ( 𝐷 ∈ ω , 𝐷 , ∅ ) ) ) |
| 37 | 7 15 22 30 36 | dedth4h | ⊢ ( ( ( 𝐴 ∈ ω ∧ 𝐵 ∈ ω ) ∧ ( 𝐶 ∈ ω ∧ 𝐷 ∈ ω ) ) → ( ( ( ( 𝐴 +o 𝐵 ) ·o ( 𝐴 +o 𝐵 ) ) +o 𝐵 ) = ( ( ( 𝐶 +o 𝐷 ) ·o ( 𝐶 +o 𝐷 ) ) +o 𝐷 ) ↔ ( 𝐴 = 𝐶 ∧ 𝐵 = 𝐷 ) ) ) |