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Theorem alexsubALTlem2 24347
Description: Lemma for alexsubALT 24350. Every subset of a base which has no finite subcover is a subset of a maximal such collection. (Contributed by Jeff Hankins, 27-Jan-2010.)
Hypothesis
Ref Expression
alexsubALT.1 𝑋 = ∪ 𝐽
Assertion
Ref Expression
alexsubALTlem2 (((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) → ∃𝑢 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})∀𝑣 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ¬ 𝑢 ⊊ 𝑣)
Distinct variable groups:   𝑎,𝑏,𝑐,𝑑,𝑢,𝑣,𝑥,𝑧,𝐽   𝑋,𝑎,𝑏,𝑐,𝑑,𝑢,𝑣,𝑥,𝑧

Proof of Theorem alexsubALTlem2
Dummy variables 𝑛 𝑤 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 ssel 3925 . . . . . . . . . . . . 13 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → (𝑤 ∈ 𝑦 → 𝑤 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})))
2 elun 4100 . . . . . . . . . . . . . . 15 (𝑤 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ↔ (𝑤 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∨ 𝑤 ∈ {∅}))
3 sseq2 3957 . . . . . . . . . . . . . . . . . 18 (𝑧 = 𝑤 → (𝑎 ⊆ 𝑧 ↔ 𝑎 ⊆ 𝑤))
4 pweq 4571 . . . . . . . . . . . . . . . . . . . 20 (𝑧 = 𝑤 → 𝒫 𝑧 = 𝒫 𝑤)
54ineq1d 4165 . . . . . . . . . . . . . . . . . . 19 (𝑧 = 𝑤 → (𝒫 𝑧 ∩ Fin) = (𝒫 𝑤 ∩ Fin))
65raleqdv 3320 . . . . . . . . . . . . . . . . . 18 (𝑧 = 𝑤 → (∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 ↔ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))
73, 6anbi12d 644 . . . . . . . . . . . . . . . . 17 (𝑧 = 𝑤 → ((𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ↔ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)))
87elrab 3645 . . . . . . . . . . . . . . . 16 (𝑤 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ↔ (𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)))
9 velsn 4600 . . . . . . . . . . . . . . . 16 (𝑤 ∈ {∅} ↔ 𝑤 = ∅)
108, 9orbi12i 928 . . . . . . . . . . . . . . 15 ((𝑤 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∨ 𝑤 ∈ {∅}) ↔ ((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) ∨ 𝑤 = ∅))
112, 10bitri 278 . . . . . . . . . . . . . 14 (𝑤 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ↔ ((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) ∨ 𝑤 = ∅))
12 elpwi 4564 . . . . . . . . . . . . . . . 16 (𝑤 ∈ 𝒫 (fi‘𝑥) → 𝑤 ⊆ (fi‘𝑥))
1312adantr 486 . . . . . . . . . . . . . . 15 ((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) → 𝑤 ⊆ (fi‘𝑥))
14 0ss 4350 . . . . . . . . . . . . . . . 16 ∅ ⊆ (fi‘𝑥)
15 sseq1 3956 . . . . . . . . . . . . . . . 16 (𝑤 = ∅ → (𝑤 ⊆ (fi‘𝑥) ↔ ∅ ⊆ (fi‘𝑥)))
1614, 15mpbiri 261 . . . . . . . . . . . . . . 15 (𝑤 = ∅ → 𝑤 ⊆ (fi‘𝑥))
1713, 16jaoi 871 . . . . . . . . . . . . . 14 (((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) ∨ 𝑤 = ∅) → 𝑤 ⊆ (fi‘𝑥))
1811, 17sylbi 220 . . . . . . . . . . . . 13 (𝑤 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → 𝑤 ⊆ (fi‘𝑥))
191, 18syl6 36 . . . . . . . . . . . 12 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → (𝑤 ∈ 𝑦 → 𝑤 ⊆ (fi‘𝑥)))
2019ralrimiv 3154 . . . . . . . . . . 11 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → ∀𝑤 ∈ 𝑦 𝑤 ⊆ (fi‘𝑥))
21 unissb 4901 . . . . . . . . . . 11 (∪ 𝑦 ⊆ (fi‘𝑥) ↔ ∀𝑤 ∈ 𝑦 𝑤 ⊆ (fi‘𝑥))
2220, 21sylibr 237 . . . . . . . . . 10 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → ∪ 𝑦 ⊆ (fi‘𝑥))
2322adantr 486 . . . . . . . . 9 ((𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦) → ∪ 𝑦 ⊆ (fi‘𝑥))
2423ad2antlr 740 . . . . . . . 8 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → ∪ 𝑦 ⊆ (fi‘𝑥))
25 vuniex 7745 . . . . . . . . 9 ∪ 𝑦 ∈ V
2625elpw 4561 . . . . . . . 8 (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ↔ ∪ 𝑦 ⊆ (fi‘𝑥))
2724, 26sylibr 237 . . . . . . 7 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → ∪ 𝑦 ∈ 𝒫 (fi‘𝑥))
28 uni0b 4894 . . . . . . . . . 10 (∪ 𝑦 = ∅ ↔ 𝑦 ⊆ {∅})
2928notbii 323 . . . . . . . . 9 (¬ ∪ 𝑦 = ∅ ↔ ¬ 𝑦 ⊆ {∅})
30 disjssun 4421 . . . . . . . . . . . . 13 ((𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) = ∅ → (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ↔ 𝑦 ⊆ {∅}))
3130biimpcd 252 . . . . . . . . . . . 12 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → ((𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) = ∅ → 𝑦 ⊆ {∅}))
3231necon3bd 2970 . . . . . . . . . . 11 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → (¬ 𝑦 ⊆ {∅} → (𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ≠ ∅))
33 n0 4300 . . . . . . . . . . . 12 ((𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ≠ ∅ ↔ ∃𝑤 𝑤 ∈ (𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}))
34 elin 3915 . . . . . . . . . . . . . . 15 (𝑤 ∈ (𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ↔ (𝑤 ∈ 𝑦 ∧ 𝑤 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}))
358anbi2i 635 . . . . . . . . . . . . . . 15 ((𝑤 ∈ 𝑦 ∧ 𝑤 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ↔ (𝑤 ∈ 𝑦 ∧ (𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))))
3634, 35bitri 278 . . . . . . . . . . . . . 14 (𝑤 ∈ (𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ↔ (𝑤 ∈ 𝑦 ∧ (𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))))
37 simprrl 793 . . . . . . . . . . . . . . 15 ((𝑤 ∈ 𝑦 ∧ (𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))) → 𝑎 ⊆ 𝑤)
38 simpl 488 . . . . . . . . . . . . . . 15 ((𝑤 ∈ 𝑦 ∧ (𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))) → 𝑤 ∈ 𝑦)
39 ssuni 4893 . . . . . . . . . . . . . . 15 ((𝑎 ⊆ 𝑤 ∧ 𝑤 ∈ 𝑦) → 𝑎 ⊆ ∪ 𝑦)
4037, 38, 39syl2anc 596 . . . . . . . . . . . . . 14 ((𝑤 ∈ 𝑦 ∧ (𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))) → 𝑎 ⊆ ∪ 𝑦)
4136, 40sylbi 220 . . . . . . . . . . . . 13 (𝑤 ∈ (𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) → 𝑎 ⊆ ∪ 𝑦)
4241exlimiv 1963 . . . . . . . . . . . 12 (∃𝑤 𝑤 ∈ (𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) → 𝑎 ⊆ ∪ 𝑦)
4333, 42sylbi 220 . . . . . . . . . . 11 ((𝑦 ∩ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ≠ ∅ → 𝑎 ⊆ ∪ 𝑦)
4432, 43syl6 36 . . . . . . . . . 10 (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → (¬ 𝑦 ⊆ {∅} → 𝑎 ⊆ ∪ 𝑦))
4544ad2antrl 741 . . . . . . . . 9 ((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) → (¬ 𝑦 ⊆ {∅} → 𝑎 ⊆ ∪ 𝑦))
4629, 45biimtrid 245 . . . . . . . 8 ((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) → (¬ ∪ 𝑦 = ∅ → 𝑎 ⊆ ∪ 𝑦))
4746imp 412 . . . . . . 7 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → 𝑎 ⊆ ∪ 𝑦)
48 elfpw 9327 . . . . . . . . . 10 (𝑛 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ↔ (𝑛 ⊆ ∪ 𝑦 ∧ 𝑛 ∈ Fin))
49 unieq 4878 . . . . . . . . . . . . . . . . . . 19 (𝑦 = ∅ → ∪ 𝑦 = ∪ ∅)
50 uni0 4896 . . . . . . . . . . . . . . . . . . 19 ∪ ∅ = ∅
5149, 50eqtrdi 2812 . . . . . . . . . . . . . . . . . 18 (𝑦 = ∅ → ∪ 𝑦 = ∅)
5251necon3bi 2982 . . . . . . . . . . . . . . . . 17 (¬ ∪ 𝑦 = ∅ → 𝑦 ≠ ∅)
5352adantr 486 . . . . . . . . . . . . . . . 16 ((¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin) → 𝑦 ≠ ∅)
5453ad2antrl 741 . . . . . . . . . . . . . . 15 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ((¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin) ∧ 𝑛 ⊆ ∪ 𝑦)) → 𝑦 ≠ ∅)
55 simplrr 790 . . . . . . . . . . . . . . 15 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ((¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin) ∧ 𝑛 ⊆ ∪ 𝑦)) → [⊊] Or 𝑦)
56 simprlr 792 . . . . . . . . . . . . . . 15 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ((¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin) ∧ 𝑛 ⊆ ∪ 𝑦)) → 𝑛 ∈ Fin)
57 simprr 785 . . . . . . . . . . . . . . 15 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ((¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin) ∧ 𝑛 ⊆ ∪ 𝑦)) → 𝑛 ⊆ ∪ 𝑦)
58 finsschain 9332 . . . . . . . . . . . . . . 15 (((𝑦 ≠ ∅ ∧ [⊊] Or 𝑦) ∧ (𝑛 ∈ Fin ∧ 𝑛 ⊆ ∪ 𝑦)) → ∃𝑤 ∈ 𝑦 𝑛 ⊆ 𝑤)
5954, 55, 56, 57, 58syl22anc 852 . . . . . . . . . . . . . 14 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ((¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin) ∧ 𝑛 ⊆ ∪ 𝑦)) → ∃𝑤 ∈ 𝑦 𝑛 ⊆ 𝑤)
6059expr 462 . . . . . . . . . . . . 13 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ (¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin)) → (𝑛 ⊆ ∪ 𝑦 → ∃𝑤 ∈ 𝑦 𝑛 ⊆ 𝑤))
61 0elpw 5317 . . . . . . . . . . . . . . . . . . . 20 ∅ ∈ 𝒫 𝑎
62 0fi 9054 . . . . . . . . . . . . . . . . . . . 20 ∅ ∈ Fin
6361, 62elini 4145 . . . . . . . . . . . . . . . . . . 19 ∅ ∈ (𝒫 𝑎 ∩ Fin)
64 unieq 4878 . . . . . . . . . . . . . . . . . . . . . 22 (𝑏 = ∅ → ∪ 𝑏 = ∪ ∅)
6564eqeq2d 2772 . . . . . . . . . . . . . . . . . . . . 21 (𝑏 = ∅ → (𝑋 = ∪ 𝑏 ↔ 𝑋 = ∪ ∅))
6665notbid 321 . . . . . . . . . . . . . . . . . . . 20 (𝑏 = ∅ → (¬ 𝑋 = ∪ 𝑏 ↔ ¬ 𝑋 = ∪ ∅))
6766rspccv 3574 . . . . . . . . . . . . . . . . . . 19 (∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → (∅ ∈ (𝒫 𝑎 ∩ Fin) → ¬ 𝑋 = ∪ ∅))
6863, 67mpi 21 . . . . . . . . . . . . . . . . . 18 (∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → ¬ 𝑋 = ∪ ∅)
69 velpw 4562 . . . . . . . . . . . . . . . . . . . . . . . . . 26 (𝑛 ∈ 𝒫 𝑤 ↔ 𝑛 ⊆ 𝑤)
70 elin 3915 . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 (𝑛 ∈ (𝒫 𝑤 ∩ Fin) ↔ (𝑛 ∈ 𝒫 𝑤 ∧ 𝑛 ∈ Fin))
71 unieq 4878 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 (𝑏 = 𝑛 → ∪ 𝑏 = ∪ 𝑛)
7271eqeq2d 2772 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 (𝑏 = 𝑛 → (𝑋 = ∪ 𝑏 ↔ 𝑋 = ∪ 𝑛))
7372notbid 321 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 (𝑏 = 𝑛 → (¬ 𝑋 = ∪ 𝑏 ↔ ¬ 𝑋 = ∪ 𝑛))
7473rspccv 3574 . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 (∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → (𝑛 ∈ (𝒫 𝑤 ∩ Fin) → ¬ 𝑋 = ∪ 𝑛))
7570, 74biimtrrid 246 . . . . . . . . . . . . . . . . . . . . . . . . . . 27 (∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → ((𝑛 ∈ 𝒫 𝑤 ∧ 𝑛 ∈ Fin) → ¬ 𝑋 = ∪ 𝑛))
7675expd 421 . . . . . . . . . . . . . . . . . . . . . . . . . 26 (∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → (𝑛 ∈ 𝒫 𝑤 → (𝑛 ∈ Fin → ¬ 𝑋 = ∪ 𝑛)))
7769, 76biimtrrid 246 . . . . . . . . . . . . . . . . . . . . . . . . 25 (∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → (𝑛 ⊆ 𝑤 → (𝑛 ∈ Fin → ¬ 𝑋 = ∪ 𝑛)))
7877com23 87 . . . . . . . . . . . . . . . . . . . . . . . 24 (∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛)))
7978ad2antll 742 . . . . . . . . . . . . . . . . . . . . . . 23 ((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛)))
8079a1i 11 . . . . . . . . . . . . . . . . . . . . . 22 (¬ 𝑋 = ∪ ∅ → ((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
81 sseq2 3957 . . . . . . . . . . . . . . . . . . . . . . . . 25 (𝑤 = ∅ → (𝑛 ⊆ 𝑤 ↔ 𝑛 ⊆ ∅))
82 ss0 4352 . . . . . . . . . . . . . . . . . . . . . . . . 25 (𝑛 ⊆ ∅ → 𝑛 = ∅)
8381, 82biimtrdi 256 . . . . . . . . . . . . . . . . . . . . . . . 24 (𝑤 = ∅ → (𝑛 ⊆ 𝑤 → 𝑛 = ∅))
84 unieq 4878 . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 (𝑛 = ∅ → ∪ 𝑛 = ∪ ∅)
8584eqeq2d 2772 . . . . . . . . . . . . . . . . . . . . . . . . . . 27 (𝑛 = ∅ → (𝑋 = ∪ 𝑛 ↔ 𝑋 = ∪ ∅))
8685notbid 321 . . . . . . . . . . . . . . . . . . . . . . . . . 26 (𝑛 = ∅ → (¬ 𝑋 = ∪ 𝑛 ↔ ¬ 𝑋 = ∪ ∅))
8786biimprcd 253 . . . . . . . . . . . . . . . . . . . . . . . . 25 (¬ 𝑋 = ∪ ∅ → (𝑛 = ∅ → ¬ 𝑋 = ∪ 𝑛))
8887a1dd 51 . . . . . . . . . . . . . . . . . . . . . . . 24 (¬ 𝑋 = ∪ ∅ → (𝑛 = ∅ → (𝑛 ∈ Fin → ¬ 𝑋 = ∪ 𝑛)))
8983, 88syl9r 79 . . . . . . . . . . . . . . . . . . . . . . 23 (¬ 𝑋 = ∪ ∅ → (𝑤 = ∅ → (𝑛 ⊆ 𝑤 → (𝑛 ∈ Fin → ¬ 𝑋 = ∪ 𝑛))))
9089com34 92 . . . . . . . . . . . . . . . . . . . . . 22 (¬ 𝑋 = ∪ ∅ → (𝑤 = ∅ → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
9180, 90jaod 873 . . . . . . . . . . . . . . . . . . . . 21 (¬ 𝑋 = ∪ ∅ → (((𝑤 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ 𝑤 ∧ ∀𝑏 ∈ (𝒫 𝑤 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)) ∨ 𝑤 = ∅) → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
9211, 91biimtrid 245 . . . . . . . . . . . . . . . . . . . 20 (¬ 𝑋 = ∪ ∅ → (𝑤 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
931, 92sylan9r 518 . . . . . . . . . . . . . . . . . . 19 ((¬ 𝑋 = ∪ ∅ ∧ 𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})) → (𝑤 ∈ 𝑦 → (𝑛 ∈ Fin → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
9493com23 87 . . . . . . . . . . . . . . . . . 18 ((¬ 𝑋 = ∪ ∅ ∧ 𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})) → (𝑛 ∈ Fin → (𝑤 ∈ 𝑦 → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
9568, 94sylan 592 . . . . . . . . . . . . . . . . 17 ((∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 ∧ 𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})) → (𝑛 ∈ Fin → (𝑤 ∈ 𝑦 → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
9695ad2ant2lr 761 . . . . . . . . . . . . . . . 16 ((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) → (𝑛 ∈ Fin → (𝑤 ∈ 𝑦 → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))))
9796imp 412 . . . . . . . . . . . . . . 15 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ 𝑛 ∈ Fin) → (𝑤 ∈ 𝑦 → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛)))
9897adantrl 729 . . . . . . . . . . . . . 14 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ (¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin)) → (𝑤 ∈ 𝑦 → (𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛)))
9998rexlimdv 3162 . . . . . . . . . . . . 13 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ (¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin)) → (∃𝑤 ∈ 𝑦 𝑛 ⊆ 𝑤 → ¬ 𝑋 = ∪ 𝑛))
10060, 99syld 48 . . . . . . . . . . . 12 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ (¬ ∪ 𝑦 = ∅ ∧ 𝑛 ∈ Fin)) → (𝑛 ⊆ ∪ 𝑦 → ¬ 𝑋 = ∪ 𝑛))
101100expr 462 . . . . . . . . . . 11 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → (𝑛 ∈ Fin → (𝑛 ⊆ ∪ 𝑦 → ¬ 𝑋 = ∪ 𝑛)))
102101impcomd 417 . . . . . . . . . 10 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → ((𝑛 ⊆ ∪ 𝑦 ∧ 𝑛 ∈ Fin) → ¬ 𝑋 = ∪ 𝑛))
10348, 102biimtrid 245 . . . . . . . . 9 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → (𝑛 ∈ (𝒫 ∪ 𝑦 ∩ Fin) → ¬ 𝑋 = ∪ 𝑛))
104103ralrimiv 3154 . . . . . . . 8 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → ∀𝑛 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑛)
105 unieq 4878 . . . . . . . . . . 11 (𝑛 = 𝑏 → ∪ 𝑛 = ∪ 𝑏)
106105eqeq2d 2772 . . . . . . . . . 10 (𝑛 = 𝑏 → (𝑋 = ∪ 𝑛 ↔ 𝑋 = ∪ 𝑏))
107106notbid 321 . . . . . . . . 9 (𝑛 = 𝑏 → (¬ 𝑋 = ∪ 𝑛 ↔ ¬ 𝑋 = ∪ 𝑏))
108107cbvralvw 3241 . . . . . . . 8 (∀𝑛 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑛 ↔ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)
109104, 108sylib 221 . . . . . . 7 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)
11027, 47, 109jca32 525 . . . . . 6 (((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) ∧ ¬ ∪ 𝑦 = ∅) → (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)))
111110ex 418 . . . . 5 ((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) → (¬ ∪ 𝑦 = ∅ → (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))))
112 orcom 884 . . . . . 6 ((∪ 𝑦 ∈ {∅} ∨ ∪ 𝑦 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ↔ (∪ 𝑦 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∨ ∪ 𝑦 ∈ {∅}))
11325elsn 4599 . . . . . . . 8 (∪ 𝑦 ∈ {∅} ↔ ∪ 𝑦 = ∅)
114 sseq2 3957 . . . . . . . . . 10 (𝑧 = ∪ 𝑦 → (𝑎 ⊆ 𝑧 ↔ 𝑎 ⊆ ∪ 𝑦))
115 pweq 4571 . . . . . . . . . . . 12 (𝑧 = ∪ 𝑦 → 𝒫 𝑧 = 𝒫 ∪ 𝑦)
116115ineq1d 4165 . . . . . . . . . . 11 (𝑧 = ∪ 𝑦 → (𝒫 𝑧 ∩ Fin) = (𝒫 ∪ 𝑦 ∩ Fin))
117116raleqdv 3320 . . . . . . . . . 10 (𝑧 = ∪ 𝑦 → (∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏 ↔ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))
118114, 117anbi12d 644 . . . . . . . . 9 (𝑧 = ∪ 𝑦 → ((𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ↔ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)))
119118elrab 3645 . . . . . . . 8 (∪ 𝑦 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ↔ (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)))
120113, 119orbi12i 928 . . . . . . 7 ((∪ 𝑦 ∈ {∅} ∨ ∪ 𝑦 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}) ↔ (∪ 𝑦 = ∅ ∨ (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))))
121 df-or 862 . . . . . . 7 ((∪ 𝑦 = ∅ ∨ (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))) ↔ (¬ ∪ 𝑦 = ∅ → (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))))
122120, 121bitr2i 279 . . . . . 6 ((¬ ∪ 𝑦 = ∅ → (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))) ↔ (∪ 𝑦 ∈ {∅} ∨ ∪ 𝑦 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)}))
123 elun 4100 . . . . . 6 (∪ 𝑦 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ↔ (∪ 𝑦 ∈ {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∨ ∪ 𝑦 ∈ {∅}))
124112, 122, 1233bitr4i 306 . . . . 5 ((¬ ∪ 𝑦 = ∅ → (∪ 𝑦 ∈ 𝒫 (fi‘𝑥) ∧ (𝑎 ⊆ ∪ 𝑦 ∧ ∀𝑏 ∈ (𝒫 ∪ 𝑦 ∩ Fin) ¬ 𝑋 = ∪ 𝑏))) ↔ ∪ 𝑦 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}))
125111, 124sylib 221 . . . 4 ((((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) ∧ (𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦)) → ∪ 𝑦 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}))
126125ex 418 . . 3 (((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) → ((𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦) → ∪ 𝑦 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})))
127126alrimiv 1960 . 2 (((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) → ∀𝑦((𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦) → ∪ 𝑦 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})))
128 fvex 6890 . . . . . 6 (fi‘𝑥) ∈ V
129128pwex 5342 . . . . 5 𝒫 (fi‘𝑥) ∈ V
130129rabex 5300 . . . 4 {𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∈ V
131 p0ex 5346 . . . 4 {∅} ∈ V
132130, 131unex 7750 . . 3 ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∈ V
133132zorn 10566 . 2 (∀𝑦((𝑦 ⊆ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ∧ [⊊] Or 𝑦) → ∪ 𝑦 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})) → ∃𝑢 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})∀𝑣 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ¬ 𝑢 ⊊ 𝑣)
134127, 133syl 18 1 (((𝐽 = (topGen‘(fi‘𝑥)) ∧ ∀𝑐 ∈ 𝒫 𝑥(𝑋 = ∪ 𝑐 → ∃𝑑 ∈ (𝒫 𝑐 ∩ Fin)𝑋 = ∪ 𝑑) ∧ 𝑎 ∈ 𝒫 (fi‘𝑥)) ∧ ∀𝑏 ∈ (𝒫 𝑎 ∩ Fin) ¬ 𝑋 = ∪ 𝑏) → ∃𝑢 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅})∀𝑣 ∈ ({𝑧 ∈ 𝒫 (fi‘𝑥) ∣ (𝑎 ⊆ 𝑧 ∧ ∀𝑏 ∈ (𝒫 𝑧 ∩ Fin) ¬ 𝑋 = ∪ 𝑏)} ∪ {∅}) ¬ 𝑢 ⊊ 𝑣)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 401   ∨ wo 861   ∧ w3a 1103  ∀wal 1568   = wceq 1570  ∃wex 1812   ∈ wcel 2145   ≠ wne 2956  ∀wral 3077  ∃wrex 3087  {crab 3413   ∪ cun 3897   ∩ cin 3898   ⊆ wss 3899   ⊊ wpss 3900  ∅c0 4279  𝒫 cpw 4557  {csn 4584  ∪ cuni 4867   Or wor 5558  ‘cfv 6531   [⊊] crpss 7727  Fincfn 8957  ficfi 9386  topGenctg 17588
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2213  ax-ext 2733  ax-rep 5232  ax-sep 5249  ax-nul 5260  ax-pow 5327  ax-pr 5391  ax-un 7740  ax-ac2 10522
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-ral 3078  df-rex 3088  df-rmo 3366  df-reu 3367  df-rab 3414  df-v 3453  df-sbc 3740  df-csb 3848  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-pss 3919  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-int 4908  df-iun 4953  df-br 5104  df-opab 5168  df-mpt 5187  df-tr 5213  df-id 5546  df-eprel 5551  df-po 5559  df-so 5560  df-fr 5604  df-se 5605  df-we 5606  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-res 5663  df-ima 5664  df-pred 6297  df-ord 6358  df-on 6359  df-lim 6360  df-suc 6361  df-iota 6487  df-fun 6533  df-fn 6534  df-f 6535  df-f1 6536  df-fo 6537  df-f1o 6538  df-fv 6539  df-isom 6540  df-riota 7369  df-ov 7415  df-rpss 7728  df-om 7867  df-2nd 7991  df-frecs 8283  df-wrecs 8314  df-recs 8363  df-en 8958  df-fin 8961  df-card 10001  df-ac 10176
This theorem is used by:  alexsubALTlem4  24349
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