| Step | Hyp | Ref
 | Expression | 
| 1 |   | vex 2766 | 
. . . . . . . . . . 11
⊢ 𝑦 ∈ V | 
| 2 | 1 | enref 6824 | 
. . . . . . . . . 10
⊢ 𝑦 ≈ 𝑦 | 
| 3 |   | 2z 9354 | 
. . . . . . . . . . 11
⊢ 2 ∈
ℤ | 
| 4 |   | uzennn 10528 | 
. . . . . . . . . . 11
⊢ (2 ∈
ℤ → (ℤ≥‘2) ≈
ℕ) | 
| 5 | 3, 4 | ax-mp 5 | 
. . . . . . . . . 10
⊢
(ℤ≥‘2) ≈ ℕ | 
| 6 |   | djuen 7278 | 
. . . . . . . . . 10
⊢ ((𝑦 ≈ 𝑦 ∧ (ℤ≥‘2)
≈ ℕ) → (𝑦
⊔ (ℤ≥‘2)) ≈ (𝑦 ⊔ ℕ)) | 
| 7 | 2, 5, 6 | mp2an 426 | 
. . . . . . . . 9
⊢ (𝑦 ⊔
(ℤ≥‘2)) ≈ (𝑦 ⊔ ℕ) | 
| 8 | 7 | ensymi 6841 | 
. . . . . . . 8
⊢ (𝑦 ⊔ ℕ) ≈
(𝑦 ⊔
(ℤ≥‘2)) | 
| 9 |   | zex 9335 | 
. . . . . . . . . . 11
⊢ ℤ
∈ V | 
| 10 |   | uzssz 9621 | 
. . . . . . . . . . 11
⊢
(ℤ≥‘2) ⊆ ℤ | 
| 11 | 9, 10 | ssexi 4171 | 
. . . . . . . . . 10
⊢
(ℤ≥‘2) ∈ V | 
| 12 |   | 1re 8025 | 
. . . . . . . . . . . . . . 15
⊢ 1 ∈
ℝ | 
| 13 | 12 | ltnri 8119 | 
. . . . . . . . . . . . . 14
⊢  ¬ 1
< 1 | 
| 14 |   | simplr 528 | 
. . . . . . . . . . . . . . . . 17
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → 𝑦 ⊆ {1}) | 
| 15 |   | simpr 110 | 
. . . . . . . . . . . . . . . . 17
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → 𝑧 ∈ 𝑦) | 
| 16 | 14, 15 | sseldd 3184 | 
. . . . . . . . . . . . . . . 16
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → 𝑧 ∈ {1}) | 
| 17 |   | elsni 3640 | 
. . . . . . . . . . . . . . . 16
⊢ (𝑧 ∈ {1} → 𝑧 = 1) | 
| 18 | 16, 17 | syl 14 | 
. . . . . . . . . . . . . . 15
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → 𝑧 = 1) | 
| 19 | 18 | breq2d 4045 | 
. . . . . . . . . . . . . 14
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → (1 < 𝑧 ↔ 1 < 1)) | 
| 20 | 13, 19 | mtbiri 676 | 
. . . . . . . . . . . . 13
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → ¬ 1 < 𝑧) | 
| 21 |   | eluz2gt1 9676 | 
. . . . . . . . . . . . 13
⊢ (𝑧 ∈
(ℤ≥‘2) → 1 < 𝑧) | 
| 22 | 20, 21 | nsyl 629 | 
. . . . . . . . . . . 12
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑧 ∈ 𝑦) → ¬ 𝑧 ∈
(ℤ≥‘2)) | 
| 23 | 22 | ralrimiva 2570 | 
. . . . . . . . . . 11
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
∀𝑧 ∈ 𝑦 ¬ 𝑧 ∈
(ℤ≥‘2)) | 
| 24 |   | disj 3499 | 
. . . . . . . . . . 11
⊢ ((𝑦 ∩
(ℤ≥‘2)) = ∅ ↔ ∀𝑧 ∈ 𝑦 ¬ 𝑧 ∈
(ℤ≥‘2)) | 
| 25 | 23, 24 | sylibr 134 | 
. . . . . . . . . 10
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 ∩
(ℤ≥‘2)) = ∅) | 
| 26 |   | endjudisj 7277 | 
. . . . . . . . . 10
⊢ ((𝑦 ∈ V ∧
(ℤ≥‘2) ∈ V ∧ (𝑦 ∩ (ℤ≥‘2)) =
∅) → (𝑦 ⊔
(ℤ≥‘2)) ≈ (𝑦 ∪
(ℤ≥‘2))) | 
| 27 | 1, 11, 25, 26 | mp3an12i 1352 | 
. . . . . . . . 9
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 ⊔
(ℤ≥‘2)) ≈ (𝑦 ∪
(ℤ≥‘2))) | 
| 28 |   | simpr 110 | 
. . . . . . . . . . . 12
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
𝑦 ⊆
{1}) | 
| 29 |   | 1nn 9001 | 
. . . . . . . . . . . . 13
⊢ 1 ∈
ℕ | 
| 30 |   | snssi 3766 | 
. . . . . . . . . . . . 13
⊢ (1 ∈
ℕ → {1} ⊆ ℕ) | 
| 31 | 29, 30 | ax-mp 5 | 
. . . . . . . . . . . 12
⊢ {1}
⊆ ℕ | 
| 32 | 28, 31 | sstrdi 3195 | 
. . . . . . . . . . 11
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
𝑦 ⊆
ℕ) | 
| 33 |   | 2nn 9152 | 
. . . . . . . . . . . 12
⊢ 2 ∈
ℕ | 
| 34 |   | uznnssnn 9651 | 
. . . . . . . . . . . 12
⊢ (2 ∈
ℕ → (ℤ≥‘2) ⊆
ℕ) | 
| 35 | 33, 34 | mp1i 10 | 
. . . . . . . . . . 11
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(ℤ≥‘2) ⊆ ℕ) | 
| 36 | 32, 35 | unssd 3339 | 
. . . . . . . . . 10
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 ∪
(ℤ≥‘2)) ⊆ ℕ) | 
| 37 |   | nfv 1542 | 
. . . . . . . . . . . . . . . 16
⊢
Ⅎ𝑚 𝑥 ⊆
ℕ | 
| 38 |   | nfra1 2528 | 
. . . . . . . . . . . . . . . 16
⊢
Ⅎ𝑚∀𝑚 ∈ ℕ ∃𝑛 ∈ 𝑥 𝑚 < 𝑛 | 
| 39 | 37, 38 | nfan 1579 | 
. . . . . . . . . . . . . . 15
⊢
Ⅎ𝑚(𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) | 
| 40 |   | nfv 1542 | 
. . . . . . . . . . . . . . 15
⊢
Ⅎ𝑚 𝑥 ≈
ℕ | 
| 41 | 39, 40 | nfim 1586 | 
. . . . . . . . . . . . . 14
⊢
Ⅎ𝑚((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) | 
| 42 | 41 | nfal 1590 | 
. . . . . . . . . . . . 13
⊢
Ⅎ𝑚∀𝑥((𝑥 ⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) | 
| 43 |   | nfv 1542 | 
. . . . . . . . . . . . 13
⊢
Ⅎ𝑚ω
∈ Omni | 
| 44 | 42, 43 | nfan 1579 | 
. . . . . . . . . . . 12
⊢
Ⅎ𝑚(∀𝑥((𝑥 ⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈
Omni) | 
| 45 |   | nfv 1542 | 
. . . . . . . . . . . 12
⊢
Ⅎ𝑚 𝑦 ⊆ {1} | 
| 46 | 44, 45 | nfan 1579 | 
. . . . . . . . . . 11
⊢
Ⅎ𝑚((∀𝑥((𝑥 ⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆
{1}) | 
| 47 |   | simpr 110 | 
. . . . . . . . . . . . . . . . 17
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
𝑚 ∈
ℕ) | 
| 48 | 47 | peano2nnd 9005 | 
. . . . . . . . . . . . . . . 16
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
(𝑚 + 1) ∈
ℕ) | 
| 49 | 48 | nnzd 9447 | 
. . . . . . . . . . . . . . 15
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
(𝑚 + 1) ∈
ℤ) | 
| 50 |   | 0p1e1 9104 | 
. . . . . . . . . . . . . . . . 17
⊢ (0 + 1) =
1 | 
| 51 |   | 0red 8027 | 
. . . . . . . . . . . . . . . . . 18
⊢ (𝑚 ∈ ℕ → 0 ∈
ℝ) | 
| 52 |   | nnre 8997 | 
. . . . . . . . . . . . . . . . . 18
⊢ (𝑚 ∈ ℕ → 𝑚 ∈
ℝ) | 
| 53 |   | 1red 8041 | 
. . . . . . . . . . . . . . . . . 18
⊢ (𝑚 ∈ ℕ → 1 ∈
ℝ) | 
| 54 |   | nngt0 9015 | 
. . . . . . . . . . . . . . . . . 18
⊢ (𝑚 ∈ ℕ → 0 <
𝑚) | 
| 55 | 51, 52, 53, 54 | ltadd1dd 8583 | 
. . . . . . . . . . . . . . . . 17
⊢ (𝑚 ∈ ℕ → (0 + 1)
< (𝑚 +
1)) | 
| 56 | 50, 55 | eqbrtrrid 4069 | 
. . . . . . . . . . . . . . . 16
⊢ (𝑚 ∈ ℕ → 1 <
(𝑚 + 1)) | 
| 57 | 56 | adantl 277 | 
. . . . . . . . . . . . . . 15
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) → 1
< (𝑚 +
1)) | 
| 58 |   | eluz2b1 9675 | 
. . . . . . . . . . . . . . 15
⊢ ((𝑚 + 1) ∈
(ℤ≥‘2) ↔ ((𝑚 + 1) ∈ ℤ ∧ 1 < (𝑚 + 1))) | 
| 59 | 49, 57, 58 | sylanbrc 417 | 
. . . . . . . . . . . . . 14
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
(𝑚 + 1) ∈
(ℤ≥‘2)) | 
| 60 |   | elun2 3331 | 
. . . . . . . . . . . . . 14
⊢ ((𝑚 + 1) ∈
(ℤ≥‘2) → (𝑚 + 1) ∈ (𝑦 ∪
(ℤ≥‘2))) | 
| 61 | 59, 60 | syl 14 | 
. . . . . . . . . . . . 13
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
(𝑚 + 1) ∈ (𝑦 ∪
(ℤ≥‘2))) | 
| 62 | 47 | nnred 9003 | 
. . . . . . . . . . . . . 14
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
𝑚 ∈
ℝ) | 
| 63 | 62 | ltp1d 8957 | 
. . . . . . . . . . . . 13
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
𝑚 < (𝑚 + 1)) | 
| 64 |   | breq2 4037 | 
. . . . . . . . . . . . . 14
⊢ (𝑛 = (𝑚 + 1) → (𝑚 < 𝑛 ↔ 𝑚 < (𝑚 + 1))) | 
| 65 | 64 | rspcev 2868 | 
. . . . . . . . . . . . 13
⊢ (((𝑚 + 1) ∈ (𝑦 ∪ (ℤ≥‘2))
∧ 𝑚 < (𝑚 + 1)) → ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛) | 
| 66 | 61, 63, 65 | syl2anc 411 | 
. . . . . . . . . . . 12
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑚 ∈ ℕ) →
∃𝑛 ∈ (𝑦 ∪
(ℤ≥‘2))𝑚 < 𝑛) | 
| 67 | 66 | ex 115 | 
. . . . . . . . . . 11
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑚 ∈ ℕ →
∃𝑛 ∈ (𝑦 ∪
(ℤ≥‘2))𝑚 < 𝑛)) | 
| 68 | 46, 67 | ralrimi 2568 | 
. . . . . . . . . 10
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
∀𝑚 ∈ ℕ
∃𝑛 ∈ (𝑦 ∪
(ℤ≥‘2))𝑚 < 𝑛) | 
| 69 | 1, 11 | unex 4476 | 
. . . . . . . . . . . 12
⊢ (𝑦 ∪
(ℤ≥‘2)) ∈ V | 
| 70 |   | sseq1 3206 | 
. . . . . . . . . . . . . 14
⊢ (𝑥 = (𝑦 ∪ (ℤ≥‘2))
→ (𝑥 ⊆ ℕ
↔ (𝑦 ∪
(ℤ≥‘2)) ⊆ ℕ)) | 
| 71 |   | rexeq 2694 | 
. . . . . . . . . . . . . . 15
⊢ (𝑥 = (𝑦 ∪ (ℤ≥‘2))
→ (∃𝑛 ∈
𝑥 𝑚 < 𝑛 ↔ ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛)) | 
| 72 | 71 | ralbidv 2497 | 
. . . . . . . . . . . . . 14
⊢ (𝑥 = (𝑦 ∪ (ℤ≥‘2))
→ (∀𝑚 ∈
ℕ ∃𝑛 ∈
𝑥 𝑚 < 𝑛 ↔ ∀𝑚 ∈ ℕ ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛)) | 
| 73 | 70, 72 | anbi12d 473 | 
. . . . . . . . . . . . 13
⊢ (𝑥 = (𝑦 ∪ (ℤ≥‘2))
→ ((𝑥 ⊆ ℕ
∧ ∀𝑚 ∈
ℕ ∃𝑛 ∈
𝑥 𝑚 < 𝑛) ↔ ((𝑦 ∪ (ℤ≥‘2))
⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛))) | 
| 74 |   | breq1 4036 | 
. . . . . . . . . . . . 13
⊢ (𝑥 = (𝑦 ∪ (ℤ≥‘2))
→ (𝑥 ≈ ℕ
↔ (𝑦 ∪
(ℤ≥‘2)) ≈ ℕ)) | 
| 75 | 73, 74 | imbi12d 234 | 
. . . . . . . . . . . 12
⊢ (𝑥 = (𝑦 ∪ (ℤ≥‘2))
→ (((𝑥 ⊆ ℕ
∧ ∀𝑚 ∈
ℕ ∃𝑛 ∈
𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ↔ (((𝑦 ∪
(ℤ≥‘2)) ⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛) → (𝑦 ∪ (ℤ≥‘2))
≈ ℕ))) | 
| 76 | 69, 75 | spcv 2858 | 
. . . . . . . . . . 11
⊢
(∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) → (((𝑦 ∪
(ℤ≥‘2)) ⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛) → (𝑦 ∪ (ℤ≥‘2))
≈ ℕ)) | 
| 77 | 76 | ad2antrr 488 | 
. . . . . . . . . 10
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(((𝑦 ∪
(ℤ≥‘2)) ⊆ ℕ ∧ ∀𝑚 ∈ ℕ ∃𝑛 ∈ (𝑦 ∪ (ℤ≥‘2))𝑚 < 𝑛) → (𝑦 ∪ (ℤ≥‘2))
≈ ℕ)) | 
| 78 | 36, 68, 77 | mp2and 433 | 
. . . . . . . . 9
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 ∪
(ℤ≥‘2)) ≈ ℕ) | 
| 79 |   | entr 6843 | 
. . . . . . . . 9
⊢ (((𝑦 ⊔
(ℤ≥‘2)) ≈ (𝑦 ∪ (ℤ≥‘2))
∧ (𝑦 ∪
(ℤ≥‘2)) ≈ ℕ) → (𝑦 ⊔ (ℤ≥‘2))
≈ ℕ) | 
| 80 | 27, 78, 79 | syl2anc 411 | 
. . . . . . . 8
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 ⊔
(ℤ≥‘2)) ≈ ℕ) | 
| 81 |   | entr 6843 | 
. . . . . . . 8
⊢ (((𝑦 ⊔ ℕ) ≈
(𝑦 ⊔
(ℤ≥‘2)) ∧ (𝑦 ⊔ (ℤ≥‘2))
≈ ℕ) → (𝑦
⊔ ℕ) ≈ ℕ) | 
| 82 | 8, 80, 81 | sylancr 414 | 
. . . . . . 7
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 ⊔ ℕ)
≈ ℕ) | 
| 83 | 82 | ensymd 6842 | 
. . . . . 6
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
ℕ ≈ (𝑦 ⊔
ℕ)) | 
| 84 |   | bren 6806 | 
. . . . . 6
⊢ (ℕ
≈ (𝑦 ⊔
ℕ) ↔ ∃𝑓
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) | 
| 85 | 83, 84 | sylib 122 | 
. . . . 5
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
∃𝑓 𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) | 
| 86 |   | simpllr 534 | 
. . . . . . . . 9
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → ω ∈
Omni) | 
| 87 |   | nnenom 10526 | 
. . . . . . . . . 10
⊢ ℕ
≈ ω | 
| 88 |   | enomni 7205 | 
. . . . . . . . . 10
⊢ (ℕ
≈ ω → (ℕ ∈ Omni ↔ ω ∈
Omni)) | 
| 89 | 87, 88 | ax-mp 5 | 
. . . . . . . . 9
⊢ (ℕ
∈ Omni ↔ ω ∈ Omni) | 
| 90 | 86, 89 | sylibr 134 | 
. . . . . . . 8
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → ℕ ∈
Omni) | 
| 91 |   | f1ofo 5511 | 
. . . . . . . . 9
⊢ (𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ) → 𝑓:ℕ–onto→(𝑦 ⊔ ℕ)) | 
| 92 | 91 | adantl 277 | 
. . . . . . . 8
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → 𝑓:ℕ–onto→(𝑦 ⊔ ℕ)) | 
| 93 | 90, 92 | fodjuomni 7215 | 
. . . . . . 7
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → (∃𝑤 𝑤 ∈ 𝑦 ∨ 𝑦 = ∅)) | 
| 94 | 93 | orcomd 730 | 
. . . . . 6
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → (𝑦 = ∅ ∨ ∃𝑤 𝑤 ∈ 𝑦)) | 
| 95 |   | simplr 528 | 
. . . . . . . 8
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → 𝑦 ⊆ {1}) | 
| 96 |   | sssnm 3784 | 
. . . . . . . 8
⊢
(∃𝑤 𝑤 ∈ 𝑦 → (𝑦 ⊆ {1} ↔ 𝑦 = {1})) | 
| 97 | 95, 96 | syl5ibcom 155 | 
. . . . . . 7
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → (∃𝑤 𝑤 ∈ 𝑦 → 𝑦 = {1})) | 
| 98 | 97 | orim2d 789 | 
. . . . . 6
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → ((𝑦 = ∅ ∨ ∃𝑤 𝑤 ∈ 𝑦) → (𝑦 = ∅ ∨ 𝑦 = {1}))) | 
| 99 | 94, 98 | mpd 13 | 
. . . . 5
⊢
((((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) ∧
𝑓:ℕ–1-1-onto→(𝑦 ⊔ ℕ)) → (𝑦 = ∅ ∨ 𝑦 = {1})) | 
| 100 | 85, 99 | exlimddv 1913 | 
. . . 4
⊢
(((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
∧ 𝑦 ⊆ {1}) →
(𝑦 = ∅ ∨ 𝑦 = {1})) | 
| 101 | 100 | ex 115 | 
. . 3
⊢
((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
→ (𝑦 ⊆ {1}
→ (𝑦 = ∅ ∨
𝑦 = {1}))) | 
| 102 | 101 | alrimiv 1888 | 
. 2
⊢
((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
→ ∀𝑦(𝑦 ⊆ {1} → (𝑦 = ∅ ∨ 𝑦 = {1}))) | 
| 103 |   | exmidsssnc 4236 | 
. . 3
⊢ (1 ∈
ℕ → (EXMID ↔ ∀𝑦(𝑦 ⊆ {1} → (𝑦 = ∅ ∨ 𝑦 = {1})))) | 
| 104 | 29, 103 | ax-mp 5 | 
. 2
⊢
(EXMID ↔ ∀𝑦(𝑦 ⊆ {1} → (𝑦 = ∅ ∨ 𝑦 = {1}))) | 
| 105 | 102, 104 | sylibr 134 | 
1
⊢
((∀𝑥((𝑥 ⊆ ℕ ∧
∀𝑚 ∈ ℕ
∃𝑛 ∈ 𝑥 𝑚 < 𝑛) → 𝑥 ≈ ℕ) ∧ ω ∈ Omni)
→ EXMID) |