| Step | Hyp | Ref
 | Expression | 
| 1 |   | ctssdclemn0.f | 
. . . . . . . . 9
⊢ (𝜑 → 𝐹:𝑆–onto→𝐴) | 
| 2 | 1 | ad2antrr 488 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑚 ∈ ω) ∧ 𝑚 ∈ 𝑆) → 𝐹:𝑆–onto→𝐴) | 
| 3 |   | fof 5480 | 
. . . . . . . 8
⊢ (𝐹:𝑆–onto→𝐴 → 𝐹:𝑆⟶𝐴) | 
| 4 | 2, 3 | syl 14 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑚 ∈ ω) ∧ 𝑚 ∈ 𝑆) → 𝐹:𝑆⟶𝐴) | 
| 5 |   | simpr 110 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑚 ∈ ω) ∧ 𝑚 ∈ 𝑆) → 𝑚 ∈ 𝑆) | 
| 6 | 4, 5 | ffvelcdmd 5698 | 
. . . . . 6
⊢ (((𝜑 ∧ 𝑚 ∈ ω) ∧ 𝑚 ∈ 𝑆) → (𝐹‘𝑚) ∈ 𝐴) | 
| 7 |   | djulcl 7117 | 
. . . . . 6
⊢ ((𝐹‘𝑚) ∈ 𝐴 → (inl‘(𝐹‘𝑚)) ∈ (𝐴 ⊔ 1o)) | 
| 8 | 6, 7 | syl 14 | 
. . . . 5
⊢ (((𝜑 ∧ 𝑚 ∈ ω) ∧ 𝑚 ∈ 𝑆) → (inl‘(𝐹‘𝑚)) ∈ (𝐴 ⊔ 1o)) | 
| 9 |   | 0lt1o 6498 | 
. . . . . . 7
⊢ ∅
∈ 1o | 
| 10 |   | djurcl 7118 | 
. . . . . . 7
⊢ (∅
∈ 1o → (inr‘∅) ∈ (𝐴 ⊔ 1o)) | 
| 11 | 9, 10 | ax-mp 5 | 
. . . . . 6
⊢
(inr‘∅) ∈ (𝐴 ⊔ 1o) | 
| 12 | 11 | a1i 9 | 
. . . . 5
⊢ (((𝜑 ∧ 𝑚 ∈ ω) ∧ ¬ 𝑚 ∈ 𝑆) → (inr‘∅) ∈ (𝐴 ⊔
1o)) | 
| 13 |   | eleq1 2259 | 
. . . . . . 7
⊢ (𝑛 = 𝑚 → (𝑛 ∈ 𝑆 ↔ 𝑚 ∈ 𝑆)) | 
| 14 | 13 | dcbid 839 | 
. . . . . 6
⊢ (𝑛 = 𝑚 → (DECID 𝑛 ∈ 𝑆 ↔ DECID 𝑚 ∈ 𝑆)) | 
| 15 |   | ctssdclemn0.dc | 
. . . . . . 7
⊢ (𝜑 → ∀𝑛 ∈ ω DECID 𝑛 ∈ 𝑆) | 
| 16 | 15 | adantr 276 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑚 ∈ ω) → ∀𝑛 ∈ ω
DECID 𝑛
∈ 𝑆) | 
| 17 |   | simpr 110 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑚 ∈ ω) → 𝑚 ∈ ω) | 
| 18 | 14, 16, 17 | rspcdva 2873 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑚 ∈ ω) → DECID
𝑚 ∈ 𝑆) | 
| 19 | 8, 12, 18 | ifcldadc 3590 | 
. . . 4
⊢ ((𝜑 ∧ 𝑚 ∈ ω) → if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)) ∈ (𝐴 ⊔
1o)) | 
| 20 | 19 | fmpttd 5717 | 
. . 3
⊢ (𝜑 → (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)),
(inr‘∅))):ω⟶(𝐴 ⊔ 1o)) | 
| 21 | 1 | ad3antrrr 492 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → 𝐹:𝑆–onto→𝐴) | 
| 22 |   | simplr 528 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → 𝑧 ∈ 𝐴) | 
| 23 |   | foelrn 5799 | 
. . . . . . . . 9
⊢ ((𝐹:𝑆–onto→𝐴 ∧ 𝑧 ∈ 𝐴) → ∃𝑦 ∈ 𝑆 𝑧 = (𝐹‘𝑦)) | 
| 24 | 21, 22, 23 | syl2anc 411 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → ∃𝑦 ∈ 𝑆 𝑧 = (𝐹‘𝑦)) | 
| 25 |   | simplr 528 | 
. . . . . . . . . . . 12
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑦 ∈ 𝑆) | 
| 26 | 25 | iftrued 3568 | 
. . . . . . . . . . 11
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → if(𝑦 ∈ 𝑆, (inl‘(𝐹‘𝑦)), (inr‘∅)) = (inl‘(𝐹‘𝑦))) | 
| 27 |   | eqid 2196 | 
. . . . . . . . . . . 12
⊢ (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))) = (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))) | 
| 28 |   | eleq1 2259 | 
. . . . . . . . . . . . 13
⊢ (𝑚 = 𝑦 → (𝑚 ∈ 𝑆 ↔ 𝑦 ∈ 𝑆)) | 
| 29 |   | 2fveq3 5563 | 
. . . . . . . . . . . . 13
⊢ (𝑚 = 𝑦 → (inl‘(𝐹‘𝑚)) = (inl‘(𝐹‘𝑦))) | 
| 30 | 28, 29 | ifbieq1d 3583 | 
. . . . . . . . . . . 12
⊢ (𝑚 = 𝑦 → if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)) = if(𝑦 ∈ 𝑆, (inl‘(𝐹‘𝑦)), (inr‘∅))) | 
| 31 |   | ctssdclemn0.ss | 
. . . . . . . . . . . . . 14
⊢ (𝜑 → 𝑆 ⊆ ω) | 
| 32 | 31 | ad5antr 496 | 
. . . . . . . . . . . . 13
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑆 ⊆ ω) | 
| 33 | 32, 25 | sseldd 3184 | 
. . . . . . . . . . . 12
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑦 ∈ ω) | 
| 34 | 1, 3 | syl 14 | 
. . . . . . . . . . . . . . . 16
⊢ (𝜑 → 𝐹:𝑆⟶𝐴) | 
| 35 | 34 | ad5antr 496 | 
. . . . . . . . . . . . . . 15
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝐹:𝑆⟶𝐴) | 
| 36 | 35, 25 | ffvelcdmd 5698 | 
. . . . . . . . . . . . . 14
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → (𝐹‘𝑦) ∈ 𝐴) | 
| 37 |   | djulcl 7117 | 
. . . . . . . . . . . . . 14
⊢ ((𝐹‘𝑦) ∈ 𝐴 → (inl‘(𝐹‘𝑦)) ∈ (𝐴 ⊔ 1o)) | 
| 38 | 36, 37 | syl 14 | 
. . . . . . . . . . . . 13
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → (inl‘(𝐹‘𝑦)) ∈ (𝐴 ⊔ 1o)) | 
| 39 | 26, 38 | eqeltrd 2273 | 
. . . . . . . . . . . 12
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → if(𝑦 ∈ 𝑆, (inl‘(𝐹‘𝑦)), (inr‘∅)) ∈ (𝐴 ⊔
1o)) | 
| 40 | 27, 30, 33, 39 | fvmptd3 5655 | 
. . . . . . . . . . 11
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦) = if(𝑦 ∈ 𝑆, (inl‘(𝐹‘𝑦)), (inr‘∅))) | 
| 41 |   | simpllr 534 | 
. . . . . . . . . . . 12
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑥 = (inl‘𝑧)) | 
| 42 |   | simpr 110 | 
. . . . . . . . . . . . 13
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑧 = (𝐹‘𝑦)) | 
| 43 | 42 | fveq2d 5562 | 
. . . . . . . . . . . 12
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → (inl‘𝑧) = (inl‘(𝐹‘𝑦))) | 
| 44 | 41, 43 | eqtrd 2229 | 
. . . . . . . . . . 11
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑥 = (inl‘(𝐹‘𝑦))) | 
| 45 | 26, 40, 44 | 3eqtr4rd 2240 | 
. . . . . . . . . 10
⊢
((((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) ∧ 𝑧 = (𝐹‘𝑦)) → 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 46 | 45 | ex 115 | 
. . . . . . . . 9
⊢
(((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) ∧ 𝑦 ∈ 𝑆) → (𝑧 = (𝐹‘𝑦) → 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 47 | 46 | reximdva 2599 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → (∃𝑦 ∈ 𝑆 𝑧 = (𝐹‘𝑦) → ∃𝑦 ∈ 𝑆 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 48 | 24, 47 | mpd 13 | 
. . . . . . 7
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → ∃𝑦 ∈ 𝑆 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 49 |   | ssrexv 3248 | 
. . . . . . . . 9
⊢ (𝑆 ⊆ ω →
(∃𝑦 ∈ 𝑆 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦) → ∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 50 | 31, 49 | syl 14 | 
. . . . . . . 8
⊢ (𝜑 → (∃𝑦 ∈ 𝑆 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦) → ∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 51 | 50 | ad3antrrr 492 | 
. . . . . . 7
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → (∃𝑦 ∈ 𝑆 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦) → ∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 52 | 48, 51 | mpd 13 | 
. . . . . 6
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 𝐴) ∧ 𝑥 = (inl‘𝑧)) → ∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 53 | 52 | rexlimdva2 2617 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) →
(∃𝑧 ∈ 𝐴 𝑥 = (inl‘𝑧) → ∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 54 |   | peano1 4630 | 
. . . . . . . 8
⊢ ∅
∈ ω | 
| 55 | 54 | a1i 9 | 
. . . . . . 7
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → ∅ ∈
ω) | 
| 56 |   | ctssdclemn0.n0 | 
. . . . . . . . . 10
⊢ (𝜑 → ¬ ∅ ∈ 𝑆) | 
| 57 | 56 | ad3antrrr 492 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → ¬ ∅ ∈
𝑆) | 
| 58 | 57 | iffalsed 3571 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → if(∅ ∈
𝑆, (inl‘(𝐹‘∅)),
(inr‘∅)) = (inr‘∅)) | 
| 59 |   | eleq1 2259 | 
. . . . . . . . . 10
⊢ (𝑚 = ∅ → (𝑚 ∈ 𝑆 ↔ ∅ ∈ 𝑆)) | 
| 60 |   | 2fveq3 5563 | 
. . . . . . . . . 10
⊢ (𝑚 = ∅ →
(inl‘(𝐹‘𝑚)) = (inl‘(𝐹‘∅))) | 
| 61 | 59, 60 | ifbieq1d 3583 | 
. . . . . . . . 9
⊢ (𝑚 = ∅ → if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)) = if(∅ ∈
𝑆, (inl‘(𝐹‘∅)),
(inr‘∅))) | 
| 62 | 58, 11 | eqeltrdi 2287 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → if(∅ ∈
𝑆, (inl‘(𝐹‘∅)),
(inr‘∅)) ∈ (𝐴 ⊔ 1o)) | 
| 63 | 27, 61, 55, 62 | fvmptd3 5655 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘∅) =
if(∅ ∈ 𝑆,
(inl‘(𝐹‘∅)),
(inr‘∅))) | 
| 64 |   | simpr 110 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → 𝑥 = (inr‘𝑧)) | 
| 65 |   | simplr 528 | 
. . . . . . . . . . 11
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → 𝑧 ∈ 1o) | 
| 66 |   | el1o 6495 | 
. . . . . . . . . . 11
⊢ (𝑧 ∈ 1o ↔
𝑧 =
∅) | 
| 67 | 65, 66 | sylib 122 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → 𝑧 = ∅) | 
| 68 | 67 | fveq2d 5562 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → (inr‘𝑧) =
(inr‘∅)) | 
| 69 | 64, 68 | eqtrd 2229 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → 𝑥 = (inr‘∅)) | 
| 70 | 58, 63, 69 | 3eqtr4rd 2240 | 
. . . . . . 7
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)),
(inr‘∅)))‘∅)) | 
| 71 |   | fveq2 5558 | 
. . . . . . . 8
⊢ (𝑦 = ∅ → ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦) = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)),
(inr‘∅)))‘∅)) | 
| 72 | 71 | rspceeqv 2886 | 
. . . . . . 7
⊢ ((∅
∈ ω ∧ 𝑥 =
((𝑚 ∈ ω ↦
if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘∅))
→ ∃𝑦 ∈
ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 73 | 55, 70, 72 | syl2anc 411 | 
. . . . . 6
⊢ ((((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) ∧ 𝑧 ∈ 1o) ∧
𝑥 = (inr‘𝑧)) → ∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 74 | 73 | rexlimdva2 2617 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) →
(∃𝑧 ∈
1o 𝑥 =
(inr‘𝑧) →
∃𝑦 ∈ ω
𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 75 |   | djur 7135 | 
. . . . . . 7
⊢ (𝑥 ∈ (𝐴 ⊔ 1o) ↔
(∃𝑧 ∈ 𝐴 𝑥 = (inl‘𝑧) ∨ ∃𝑧 ∈ 1o 𝑥 = (inr‘𝑧))) | 
| 76 | 75 | biimpi 120 | 
. . . . . 6
⊢ (𝑥 ∈ (𝐴 ⊔ 1o) →
(∃𝑧 ∈ 𝐴 𝑥 = (inl‘𝑧) ∨ ∃𝑧 ∈ 1o 𝑥 = (inr‘𝑧))) | 
| 77 | 76 | adantl 277 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) →
(∃𝑧 ∈ 𝐴 𝑥 = (inl‘𝑧) ∨ ∃𝑧 ∈ 1o 𝑥 = (inr‘𝑧))) | 
| 78 | 53, 74, 77 | mpjaod 719 | 
. . . 4
⊢ ((𝜑 ∧ 𝑥 ∈ (𝐴 ⊔ 1o)) →
∃𝑦 ∈ ω
𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 79 | 78 | ralrimiva 2570 | 
. . 3
⊢ (𝜑 → ∀𝑥 ∈ (𝐴 ⊔ 1o)∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦)) | 
| 80 |   | dffo3 5709 | 
. . 3
⊢ ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))):ω–onto→(𝐴 ⊔ 1o) ↔ ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)),
(inr‘∅))):ω⟶(𝐴 ⊔ 1o) ∧ ∀𝑥 ∈ (𝐴 ⊔ 1o)∃𝑦 ∈ ω 𝑥 = ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅)))‘𝑦))) | 
| 81 | 20, 79, 80 | sylanbrc 417 | 
. 2
⊢ (𝜑 → (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))):ω–onto→(𝐴 ⊔ 1o)) | 
| 82 |   | omex 4629 | 
. . . 4
⊢ ω
∈ V | 
| 83 | 82 | mptex 5788 | 
. . 3
⊢ (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))) ∈
V | 
| 84 |   | foeq1 5476 | 
. . 3
⊢ (𝑔 = (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))) → (𝑔:ω–onto→(𝐴 ⊔ 1o) ↔ (𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))):ω–onto→(𝐴 ⊔ 1o))) | 
| 85 | 83, 84 | spcev 2859 | 
. 2
⊢ ((𝑚 ∈ ω ↦ if(𝑚 ∈ 𝑆, (inl‘(𝐹‘𝑚)), (inr‘∅))):ω–onto→(𝐴 ⊔ 1o) → ∃𝑔 𝑔:ω–onto→(𝐴 ⊔ 1o)) | 
| 86 | 81, 85 | syl 14 | 
1
⊢ (𝜑 → ∃𝑔 𝑔:ω–onto→(𝐴 ⊔ 1o)) |