Proof of Theorem nlly2i
| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | nllyi 23484 | . 2
⊢ ((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) → ∃𝑠 ∈ ((nei‘𝐽)‘{𝑃})(𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴)) | 
| 2 |  | simprrl 780 | . . 3
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → 𝑠 ⊆ 𝑈) | 
| 3 |  | velpw 4604 | . . 3
⊢ (𝑠 ∈ 𝒫 𝑈 ↔ 𝑠 ⊆ 𝑈) | 
| 4 | 2, 3 | sylibr 234 | . 2
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → 𝑠 ∈ 𝒫 𝑈) | 
| 5 |  | simpl1 1191 | . . . . 5
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → 𝐽 ∈ 𝑛-Locally 𝐴) | 
| 6 |  | nllytop 23482 | . . . . 5
⊢ (𝐽 ∈ 𝑛-Locally 𝐴 → 𝐽 ∈ Top) | 
| 7 | 5, 6 | syl 17 | . . . 4
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → 𝐽 ∈ Top) | 
| 8 |  | simprl 770 | . . . 4
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → 𝑠 ∈ ((nei‘𝐽)‘{𝑃})) | 
| 9 |  | neii2 23117 | . . . 4
⊢ ((𝐽 ∈ Top ∧ 𝑠 ∈ ((nei‘𝐽)‘{𝑃})) → ∃𝑢 ∈ 𝐽 ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) | 
| 10 | 7, 8, 9 | syl2anc 584 | . . 3
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → ∃𝑢 ∈ 𝐽 ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) | 
| 11 |  | simprl 770 | . . . . . . 7
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → {𝑃} ⊆ 𝑢) | 
| 12 |  | simpll3 1214 | . . . . . . . 8
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → 𝑃 ∈ 𝑈) | 
| 13 |  | snssg 4782 | . . . . . . . 8
⊢ (𝑃 ∈ 𝑈 → (𝑃 ∈ 𝑢 ↔ {𝑃} ⊆ 𝑢)) | 
| 14 | 12, 13 | syl 17 | . . . . . . 7
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → (𝑃 ∈ 𝑢 ↔ {𝑃} ⊆ 𝑢)) | 
| 15 | 11, 14 | mpbird 257 | . . . . . 6
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → 𝑃 ∈ 𝑢) | 
| 16 |  | simprr 772 | . . . . . 6
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → 𝑢 ⊆ 𝑠) | 
| 17 |  | simprrr 781 | . . . . . . 7
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → (𝐽 ↾t 𝑠) ∈ 𝐴) | 
| 18 | 17 | adantr 480 | . . . . . 6
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → (𝐽 ↾t 𝑠) ∈ 𝐴) | 
| 19 | 15, 16, 18 | 3jca 1128 | . . . . 5
⊢ ((((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) ∧ ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠)) → (𝑃 ∈ 𝑢 ∧ 𝑢 ⊆ 𝑠 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴)) | 
| 20 | 19 | ex 412 | . . . 4
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → (({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠) → (𝑃 ∈ 𝑢 ∧ 𝑢 ⊆ 𝑠 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) | 
| 21 | 20 | reximdv 3169 | . . 3
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → (∃𝑢 ∈ 𝐽 ({𝑃} ⊆ 𝑢 ∧ 𝑢 ⊆ 𝑠) → ∃𝑢 ∈ 𝐽 (𝑃 ∈ 𝑢 ∧ 𝑢 ⊆ 𝑠 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) | 
| 22 | 10, 21 | mpd 15 | . 2
⊢ (((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) ∧ (𝑠 ∈ ((nei‘𝐽)‘{𝑃}) ∧ (𝑠 ⊆ 𝑈 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴))) → ∃𝑢 ∈ 𝐽 (𝑃 ∈ 𝑢 ∧ 𝑢 ⊆ 𝑠 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴)) | 
| 23 | 1, 4, 22 | reximssdv 3172 | 1
⊢ ((𝐽 ∈ 𝑛-Locally 𝐴 ∧ 𝑈 ∈ 𝐽 ∧ 𝑃 ∈ 𝑈) → ∃𝑠 ∈ 𝒫 𝑈∃𝑢 ∈ 𝐽 (𝑃 ∈ 𝑢 ∧ 𝑢 ⊆ 𝑠 ∧ (𝐽 ↾t 𝑠) ∈ 𝐴)) |