| Step |
Hyp |
Ref |
Expression |
| 1 |
|
sadval.a |
⊢ ( 𝜑 → 𝐴 ⊆ ℕ0 ) |
| 2 |
|
sadval.b |
⊢ ( 𝜑 → 𝐵 ⊆ ℕ0 ) |
| 3 |
|
sadval.c |
⊢ 𝐶 = seq 0 ( ( 𝑐 ∈ 2o , 𝑚 ∈ ℕ0 ↦ if ( cadd ( 𝑚 ∈ 𝐴 , 𝑚 ∈ 𝐵 , ∅ ∈ 𝑐 ) , 1o , ∅ ) ) , ( 𝑛 ∈ ℕ0 ↦ if ( 𝑛 = 0 , ∅ , ( 𝑛 − 1 ) ) ) ) |
| 4 |
|
sadcp1.n |
⊢ ( 𝜑 → 𝑁 ∈ ℕ0 ) |
| 5 |
1 2 3
|
sadfval |
⊢ ( 𝜑 → ( 𝐴 sadd 𝐵 ) = { 𝑘 ∈ ℕ0 ∣ hadd ( 𝑘 ∈ 𝐴 , 𝑘 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑘 ) ) } ) |
| 6 |
5
|
eleq2d |
⊢ ( 𝜑 → ( 𝑁 ∈ ( 𝐴 sadd 𝐵 ) ↔ 𝑁 ∈ { 𝑘 ∈ ℕ0 ∣ hadd ( 𝑘 ∈ 𝐴 , 𝑘 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑘 ) ) } ) ) |
| 7 |
|
eleq1 |
⊢ ( 𝑘 = 𝑁 → ( 𝑘 ∈ 𝐴 ↔ 𝑁 ∈ 𝐴 ) ) |
| 8 |
|
eleq1 |
⊢ ( 𝑘 = 𝑁 → ( 𝑘 ∈ 𝐵 ↔ 𝑁 ∈ 𝐵 ) ) |
| 9 |
|
fveq2 |
⊢ ( 𝑘 = 𝑁 → ( 𝐶 ‘ 𝑘 ) = ( 𝐶 ‘ 𝑁 ) ) |
| 10 |
9
|
eleq2d |
⊢ ( 𝑘 = 𝑁 → ( ∅ ∈ ( 𝐶 ‘ 𝑘 ) ↔ ∅ ∈ ( 𝐶 ‘ 𝑁 ) ) ) |
| 11 |
7 8 10
|
hadbi123d |
⊢ ( 𝑘 = 𝑁 → ( hadd ( 𝑘 ∈ 𝐴 , 𝑘 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑘 ) ) ↔ hadd ( 𝑁 ∈ 𝐴 , 𝑁 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑁 ) ) ) ) |
| 12 |
11
|
elrab3 |
⊢ ( 𝑁 ∈ ℕ0 → ( 𝑁 ∈ { 𝑘 ∈ ℕ0 ∣ hadd ( 𝑘 ∈ 𝐴 , 𝑘 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑘 ) ) } ↔ hadd ( 𝑁 ∈ 𝐴 , 𝑁 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑁 ) ) ) ) |
| 13 |
4 12
|
syl |
⊢ ( 𝜑 → ( 𝑁 ∈ { 𝑘 ∈ ℕ0 ∣ hadd ( 𝑘 ∈ 𝐴 , 𝑘 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑘 ) ) } ↔ hadd ( 𝑁 ∈ 𝐴 , 𝑁 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑁 ) ) ) ) |
| 14 |
6 13
|
bitrd |
⊢ ( 𝜑 → ( 𝑁 ∈ ( 𝐴 sadd 𝐵 ) ↔ hadd ( 𝑁 ∈ 𝐴 , 𝑁 ∈ 𝐵 , ∅ ∈ ( 𝐶 ‘ 𝑁 ) ) ) ) |