| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | onelon 6408 | . . . . . 6
⊢ ((𝐵 ∈ On ∧ 𝐴 ∈ 𝐵) → 𝐴 ∈ On) | 
| 2 | 1 | ex 412 | . . . . 5
⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → 𝐴 ∈ On)) | 
| 3 |  | eleq2 2829 | . . . . . . . . . 10
⊢ (𝑥 = ∅ → (𝐴 ∈ 𝑥 ↔ 𝐴 ∈ ∅)) | 
| 4 |  | oveq2 7440 | . . . . . . . . . . 11
⊢ (𝑥 = ∅ → (𝐶 ·o 𝑥) = (𝐶 ·o
∅)) | 
| 5 | 4 | eleq2d 2826 | . . . . . . . . . 10
⊢ (𝑥 = ∅ → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o
∅))) | 
| 6 | 3, 5 | imbi12d 344 | . . . . . . . . 9
⊢ (𝑥 = ∅ → ((𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)) ↔ (𝐴 ∈ ∅ → (𝐶 ·o 𝐴) ∈ (𝐶 ·o
∅)))) | 
| 7 |  | eleq2 2829 | . . . . . . . . . 10
⊢ (𝑥 = 𝑦 → (𝐴 ∈ 𝑥 ↔ 𝐴 ∈ 𝑦)) | 
| 8 |  | oveq2 7440 | . . . . . . . . . . 11
⊢ (𝑥 = 𝑦 → (𝐶 ·o 𝑥) = (𝐶 ·o 𝑦)) | 
| 9 | 8 | eleq2d 2826 | . . . . . . . . . 10
⊢ (𝑥 = 𝑦 → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦))) | 
| 10 | 7, 9 | imbi12d 344 | . . . . . . . . 9
⊢ (𝑥 = 𝑦 → ((𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)) ↔ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) | 
| 11 |  | eleq2 2829 | . . . . . . . . . 10
⊢ (𝑥 = suc 𝑦 → (𝐴 ∈ 𝑥 ↔ 𝐴 ∈ suc 𝑦)) | 
| 12 |  | oveq2 7440 | . . . . . . . . . . 11
⊢ (𝑥 = suc 𝑦 → (𝐶 ·o 𝑥) = (𝐶 ·o suc 𝑦)) | 
| 13 | 12 | eleq2d 2826 | . . . . . . . . . 10
⊢ (𝑥 = suc 𝑦 → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦))) | 
| 14 | 11, 13 | imbi12d 344 | . . . . . . . . 9
⊢ (𝑥 = suc 𝑦 → ((𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)) ↔ (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦)))) | 
| 15 |  | eleq2 2829 | . . . . . . . . . 10
⊢ (𝑥 = 𝐵 → (𝐴 ∈ 𝑥 ↔ 𝐴 ∈ 𝐵)) | 
| 16 |  | oveq2 7440 | . . . . . . . . . . 11
⊢ (𝑥 = 𝐵 → (𝐶 ·o 𝑥) = (𝐶 ·o 𝐵)) | 
| 17 | 16 | eleq2d 2826 | . . . . . . . . . 10
⊢ (𝑥 = 𝐵 → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥) ↔ (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))) | 
| 18 | 15, 17 | imbi12d 344 | . . . . . . . . 9
⊢ (𝑥 = 𝐵 → ((𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)) ↔ (𝐴 ∈ 𝐵 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))) | 
| 19 |  | noel 4337 | . . . . . . . . . . 11
⊢  ¬
𝐴 ∈
∅ | 
| 20 | 19 | pm2.21i 119 | . . . . . . . . . 10
⊢ (𝐴 ∈ ∅ → (𝐶 ·o 𝐴) ∈ (𝐶 ·o
∅)) | 
| 21 | 20 | a1i 11 | . . . . . . . . 9
⊢ (((𝐴 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (𝐴 ∈ ∅ → (𝐶 ·o 𝐴) ∈ (𝐶 ·o
∅))) | 
| 22 |  | elsuci 6450 | . . . . . . . . . . . . . . 15
⊢ (𝐴 ∈ suc 𝑦 → (𝐴 ∈ 𝑦 ∨ 𝐴 = 𝑦)) | 
| 23 |  | omcl 8575 | . . . . . . . . . . . . . . . . 17
⊢ ((𝐶 ∈ On ∧ 𝑦 ∈ On) → (𝐶 ·o 𝑦) ∈ On) | 
| 24 |  | simpl 482 | . . . . . . . . . . . . . . . . 17
⊢ ((𝐶 ∈ On ∧ 𝑦 ∈ On) → 𝐶 ∈ On) | 
| 25 | 23, 24 | jca 511 | . . . . . . . . . . . . . . . 16
⊢ ((𝐶 ∈ On ∧ 𝑦 ∈ On) → ((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On)) | 
| 26 |  | oaword1 8591 | . . . . . . . . . . . . . . . . . . . . 21
⊢ (((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) → (𝐶 ·o 𝑦) ⊆ ((𝐶 ·o 𝑦) +o 𝐶)) | 
| 27 | 26 | sseld 3981 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦) → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 28 | 27 | imim2d 57 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) → ((𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)) → (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶)))) | 
| 29 | 28 | imp 406 | . . . . . . . . . . . . . . . . . 18
⊢ ((((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦))) → (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 30 | 29 | adantrl 716 | . . . . . . . . . . . . . . . . 17
⊢ ((((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 31 |  | oaord1 8590 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) → (∅
∈ 𝐶 ↔ (𝐶 ·o 𝑦) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 32 | 31 | biimpa 476 | . . . . . . . . . . . . . . . . . . 19
⊢ ((((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (𝐶 ·o 𝑦) ∈ ((𝐶 ·o 𝑦) +o 𝐶)) | 
| 33 |  | oveq2 7440 | . . . . . . . . . . . . . . . . . . . 20
⊢ (𝐴 = 𝑦 → (𝐶 ·o 𝐴) = (𝐶 ·o 𝑦)) | 
| 34 | 33 | eleq1d 2825 | . . . . . . . . . . . . . . . . . . 19
⊢ (𝐴 = 𝑦 → ((𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶) ↔ (𝐶 ·o 𝑦) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 35 | 32, 34 | syl5ibrcom 247 | . . . . . . . . . . . . . . . . . 18
⊢ ((((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (𝐴 = 𝑦 → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 36 | 35 | adantrr 717 | . . . . . . . . . . . . . . . . 17
⊢ ((((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → (𝐴 = 𝑦 → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 37 | 30, 36 | jaod 859 | . . . . . . . . . . . . . . . 16
⊢ ((((𝐶 ·o 𝑦) ∈ On ∧ 𝐶 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → ((𝐴 ∈ 𝑦 ∨ 𝐴 = 𝑦) → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 38 | 25, 37 | sylan 580 | . . . . . . . . . . . . . . 15
⊢ (((𝐶 ∈ On ∧ 𝑦 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → ((𝐴 ∈ 𝑦 ∨ 𝐴 = 𝑦) → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 39 | 22, 38 | syl5 34 | . . . . . . . . . . . . . 14
⊢ (((𝐶 ∈ On ∧ 𝑦 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 40 |  | omsuc 8565 | . . . . . . . . . . . . . . . 16
⊢ ((𝐶 ∈ On ∧ 𝑦 ∈ On) → (𝐶 ·o suc 𝑦) = ((𝐶 ·o 𝑦) +o 𝐶)) | 
| 41 | 40 | eleq2d 2826 | . . . . . . . . . . . . . . 15
⊢ ((𝐶 ∈ On ∧ 𝑦 ∈ On) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦) ↔ (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 42 | 41 | adantr 480 | . . . . . . . . . . . . . 14
⊢ (((𝐶 ∈ On ∧ 𝑦 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → ((𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦) ↔ (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝑦) +o 𝐶))) | 
| 43 | 39, 42 | sylibrd 259 | . . . . . . . . . . . . 13
⊢ (((𝐶 ∈ On ∧ 𝑦 ∈ On) ∧ (∅
∈ 𝐶 ∧ (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)))) → (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦))) | 
| 44 | 43 | exp43 436 | . . . . . . . . . . . 12
⊢ (𝐶 ∈ On → (𝑦 ∈ On → (∅
∈ 𝐶 → ((𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)) → (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦)))))) | 
| 45 | 44 | com12 32 | . . . . . . . . . . 11
⊢ (𝑦 ∈ On → (𝐶 ∈ On → (∅
∈ 𝐶 → ((𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)) → (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦)))))) | 
| 46 | 45 | adantld 490 | . . . . . . . . . 10
⊢ (𝑦 ∈ On → ((𝐴 ∈ On ∧ 𝐶 ∈ On) → (∅
∈ 𝐶 → ((𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)) → (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦)))))) | 
| 47 | 46 | impd 410 | . . . . . . . . 9
⊢ (𝑦 ∈ On → (((𝐴 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → ((𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)) → (𝐴 ∈ suc 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝑦))))) | 
| 48 |  | id 22 | . . . . . . . . . . . . . . . 16
⊢ ((𝐶 ∈ On ∧ Lim 𝑥) → (𝐶 ∈ On ∧ Lim 𝑥)) | 
| 49 | 48 | ad2ant2r 747 | . . . . . . . . . . . . . . 15
⊢ (((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ (Lim 𝑥 ∧ ∅ ∈ 𝐶)) → (𝐶 ∈ On ∧ Lim 𝑥)) | 
| 50 |  | limsuc 7871 | . . . . . . . . . . . . . . . . . . 19
⊢ (Lim
𝑥 → (𝐴 ∈ 𝑥 ↔ suc 𝐴 ∈ 𝑥)) | 
| 51 | 50 | biimpa 476 | . . . . . . . . . . . . . . . . . 18
⊢ ((Lim
𝑥 ∧ 𝐴 ∈ 𝑥) → suc 𝐴 ∈ 𝑥) | 
| 52 |  | oveq2 7440 | . . . . . . . . . . . . . . . . . . 19
⊢ (𝑦 = suc 𝐴 → (𝐶 ·o 𝑦) = (𝐶 ·o suc 𝐴)) | 
| 53 | 52 | ssiun2s 5047 | . . . . . . . . . . . . . . . . . 18
⊢ (suc
𝐴 ∈ 𝑥 → (𝐶 ·o suc 𝐴) ⊆ ∪ 𝑦 ∈ 𝑥 (𝐶 ·o 𝑦)) | 
| 54 | 51, 53 | syl 17 | . . . . . . . . . . . . . . . . 17
⊢ ((Lim
𝑥 ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o suc 𝐴) ⊆ ∪ 𝑦 ∈ 𝑥 (𝐶 ·o 𝑦)) | 
| 55 | 54 | adantll 714 | . . . . . . . . . . . . . . . 16
⊢ (((𝐶 ∈ On ∧ Lim 𝑥) ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o suc 𝐴) ⊆ ∪ 𝑦 ∈ 𝑥 (𝐶 ·o 𝑦)) | 
| 56 |  | vex 3483 | . . . . . . . . . . . . . . . . . 18
⊢ 𝑥 ∈ V | 
| 57 |  | omlim 8572 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝐶 ∈ On ∧ (𝑥 ∈ V ∧ Lim 𝑥)) → (𝐶 ·o 𝑥) = ∪ 𝑦 ∈ 𝑥 (𝐶 ·o 𝑦)) | 
| 58 | 56, 57 | mpanr1 703 | . . . . . . . . . . . . . . . . 17
⊢ ((𝐶 ∈ On ∧ Lim 𝑥) → (𝐶 ·o 𝑥) = ∪ 𝑦 ∈ 𝑥 (𝐶 ·o 𝑦)) | 
| 59 | 58 | adantr 480 | . . . . . . . . . . . . . . . 16
⊢ (((𝐶 ∈ On ∧ Lim 𝑥) ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o 𝑥) = ∪ 𝑦 ∈ 𝑥 (𝐶 ·o 𝑦)) | 
| 60 | 55, 59 | sseqtrrd 4020 | . . . . . . . . . . . . . . 15
⊢ (((𝐶 ∈ On ∧ Lim 𝑥) ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o suc 𝐴) ⊆ (𝐶 ·o 𝑥)) | 
| 61 | 49, 60 | sylan 580 | . . . . . . . . . . . . . 14
⊢ ((((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ (Lim 𝑥 ∧ ∅ ∈ 𝐶)) ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o suc 𝐴) ⊆ (𝐶 ·o 𝑥)) | 
| 62 |  | omcl 8575 | . . . . . . . . . . . . . . . . . . . 20
⊢ ((𝐶 ∈ On ∧ 𝐴 ∈ On) → (𝐶 ·o 𝐴) ∈ On) | 
| 63 |  | oaord1 8590 | . . . . . . . . . . . . . . . . . . . 20
⊢ (((𝐶 ·o 𝐴) ∈ On ∧ 𝐶 ∈ On) → (∅
∈ 𝐶 ↔ (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝐴) +o 𝐶))) | 
| 64 | 62, 63 | sylan 580 | . . . . . . . . . . . . . . . . . . 19
⊢ (((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ 𝐶 ∈ On) → (∅
∈ 𝐶 ↔ (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝐴) +o 𝐶))) | 
| 65 | 64 | anabss1 666 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝐶 ∈ On ∧ 𝐴 ∈ On) → (∅
∈ 𝐶 ↔ (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝐴) +o 𝐶))) | 
| 66 | 65 | biimpa 476 | . . . . . . . . . . . . . . . . 17
⊢ (((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ ∅ ∈
𝐶) → (𝐶 ·o 𝐴) ∈ ((𝐶 ·o 𝐴) +o 𝐶)) | 
| 67 |  | omsuc 8565 | . . . . . . . . . . . . . . . . . 18
⊢ ((𝐶 ∈ On ∧ 𝐴 ∈ On) → (𝐶 ·o suc 𝐴) = ((𝐶 ·o 𝐴) +o 𝐶)) | 
| 68 | 67 | adantr 480 | . . . . . . . . . . . . . . . . 17
⊢ (((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ ∅ ∈
𝐶) → (𝐶 ·o suc 𝐴) = ((𝐶 ·o 𝐴) +o 𝐶)) | 
| 69 | 66, 68 | eleqtrrd 2843 | . . . . . . . . . . . . . . . 16
⊢ (((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ ∅ ∈
𝐶) → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝐴)) | 
| 70 | 69 | adantrl 716 | . . . . . . . . . . . . . . 15
⊢ (((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ (Lim 𝑥 ∧ ∅ ∈ 𝐶)) → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝐴)) | 
| 71 | 70 | adantr 480 | . . . . . . . . . . . . . 14
⊢ ((((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ (Lim 𝑥 ∧ ∅ ∈ 𝐶)) ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o 𝐴) ∈ (𝐶 ·o suc 𝐴)) | 
| 72 | 61, 71 | sseldd 3983 | . . . . . . . . . . . . 13
⊢ ((((𝐶 ∈ On ∧ 𝐴 ∈ On) ∧ (Lim 𝑥 ∧ ∅ ∈ 𝐶)) ∧ 𝐴 ∈ 𝑥) → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)) | 
| 73 | 72 | exp53 447 | . . . . . . . . . . . 12
⊢ (𝐶 ∈ On → (𝐴 ∈ On → (Lim 𝑥 → (∅ ∈ 𝐶 → (𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)))))) | 
| 74 | 73 | com13 88 | . . . . . . . . . . 11
⊢ (Lim
𝑥 → (𝐴 ∈ On → (𝐶 ∈ On → (∅ ∈ 𝐶 → (𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)))))) | 
| 75 | 74 | imp4c 423 | . . . . . . . . . 10
⊢ (Lim
𝑥 → (((𝐴 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥)))) | 
| 76 | 75 | a1dd 50 | . . . . . . . . 9
⊢ (Lim
𝑥 → (((𝐴 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (∀𝑦 ∈ 𝑥 (𝐴 ∈ 𝑦 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑦)) → (𝐴 ∈ 𝑥 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝑥))))) | 
| 77 | 6, 10, 14, 18, 21, 47, 76 | tfinds3 7887 | . . . . . . . 8
⊢ (𝐵 ∈ On → (((𝐴 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (𝐴 ∈ 𝐵 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))) | 
| 78 | 77 | com23 86 | . . . . . . 7
⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → (((𝐴 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈ 𝐶) → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))) | 
| 79 | 78 | exp4a 431 | . . . . . 6
⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → ((𝐴 ∈ On ∧ 𝐶 ∈ On) → (∅ ∈ 𝐶 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))))) | 
| 80 | 79 | exp4a 431 | . . . . 5
⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → (𝐴 ∈ On → (𝐶 ∈ On → (∅ ∈ 𝐶 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵)))))) | 
| 81 | 2, 80 | mpdd 43 | . . . 4
⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → (𝐶 ∈ On → (∅ ∈ 𝐶 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))))) | 
| 82 | 81 | com34 91 | . . 3
⊢ (𝐵 ∈ On → (𝐴 ∈ 𝐵 → (∅ ∈ 𝐶 → (𝐶 ∈ On → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))))) | 
| 83 | 82 | com24 95 | . 2
⊢ (𝐵 ∈ On → (𝐶 ∈ On → (∅
∈ 𝐶 → (𝐴 ∈ 𝐵 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))))) | 
| 84 | 83 | imp31 417 | 1
⊢ (((𝐵 ∈ On ∧ 𝐶 ∈ On) ∧ ∅ ∈
𝐶) → (𝐴 ∈ 𝐵 → (𝐶 ·o 𝐴) ∈ (𝐶 ·o 𝐵))) |