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Theorem fin23lem28 10409
Description: Lemma for fin23 10458. The residual is also one-to-one. This preserves the induction invariant. (Contributed by Stefan O'Rear, 2-Nov-2014.)
Hypotheses
Ref Expression
fin23lem.a 𝑈 = seqω((𝑖 ∈ ω, 𝑢 ∈ V ↦ if(((𝑡𝑖) ∩ 𝑢) = ∅, 𝑢, ((𝑡𝑖) ∩ 𝑢))), ran 𝑡)
fin23lem17.f 𝐹 = {𝑔 ∣ ∀𝑎 ∈ (𝒫 𝑔m ω)(∀𝑥 ∈ ω (𝑎‘suc 𝑥) ⊆ (𝑎𝑥) → ran 𝑎 ∈ ran 𝑎)}
fin23lem.b 𝑃 = {𝑣 ∈ ω ∣ ran 𝑈 ⊆ (𝑡𝑣)}
fin23lem.c 𝑄 = (𝑤 ∈ ω ↦ (𝑥𝑃 (𝑥𝑃) ≈ 𝑤))
fin23lem.d 𝑅 = (𝑤 ∈ ω ↦ (𝑥 ∈ (ω ∖ 𝑃)(𝑥 ∩ (ω ∖ 𝑃)) ≈ 𝑤))
fin23lem.e 𝑍 = if(𝑃 ∈ Fin, (𝑡𝑅), ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄))
Assertion
Ref Expression
fin23lem28 (𝑡:ω–1-1→V → 𝑍:ω–1-1→V)
Distinct variable groups:   𝑔,𝑖,𝑡,𝑢,𝑣,𝑥,𝑧,𝑎   𝐹,𝑎,𝑡   𝑤,𝑎,𝑥,𝑧,𝑃   𝑣,𝑎,𝑅,𝑖,𝑢   𝑈,𝑎,𝑖,𝑢,𝑣,𝑧   𝑍,𝑎   𝑔,𝑎
Allowed substitution hints:   𝑃(𝑣,𝑢,𝑡,𝑔,𝑖)   𝑄(𝑥,𝑧,𝑤,𝑣,𝑢,𝑡,𝑔,𝑖,𝑎)   𝑅(𝑥,𝑧,𝑤,𝑡,𝑔)   𝑈(𝑥,𝑤,𝑡,𝑔)   𝐹(𝑥,𝑧,𝑤,𝑣,𝑢,𝑔,𝑖)   𝑍(𝑥,𝑧,𝑤,𝑣,𝑢,𝑡,𝑔,𝑖)

Proof of Theorem fin23lem28
Dummy variable 𝑏 is distinct from all other variables.
StepHypRef Expression
1 fin23lem.e . . 3 𝑍 = if(𝑃 ∈ Fin, (𝑡𝑅), ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄))
2 eqif 4589 . . 3 (𝑍 = if(𝑃 ∈ Fin, (𝑡𝑅), ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄)) ↔ ((𝑃 ∈ Fin ∧ 𝑍 = (𝑡𝑅)) ∨ (¬ 𝑃 ∈ Fin ∧ 𝑍 = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄))))
31, 2mpbi 230 . 2 ((𝑃 ∈ Fin ∧ 𝑍 = (𝑡𝑅)) ∨ (¬ 𝑃 ∈ Fin ∧ 𝑍 = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄)))
4 difss 4159 . . . . . . . . 9 (ω ∖ 𝑃) ⊆ ω
5 ominf 9321 . . . . . . . . . 10 ¬ ω ∈ Fin
6 fin23lem.b . . . . . . . . . . . . . 14 𝑃 = {𝑣 ∈ ω ∣ ran 𝑈 ⊆ (𝑡𝑣)}
76ssrab3 4105 . . . . . . . . . . . . 13 𝑃 ⊆ ω
8 undif 4505 . . . . . . . . . . . . 13 (𝑃 ⊆ ω ↔ (𝑃 ∪ (ω ∖ 𝑃)) = ω)
97, 8mpbi 230 . . . . . . . . . . . 12 (𝑃 ∪ (ω ∖ 𝑃)) = ω
10 unfi 9238 . . . . . . . . . . . 12 ((𝑃 ∈ Fin ∧ (ω ∖ 𝑃) ∈ Fin) → (𝑃 ∪ (ω ∖ 𝑃)) ∈ Fin)
119, 10eqeltrrid 2849 . . . . . . . . . . 11 ((𝑃 ∈ Fin ∧ (ω ∖ 𝑃) ∈ Fin) → ω ∈ Fin)
1211ex 412 . . . . . . . . . 10 (𝑃 ∈ Fin → ((ω ∖ 𝑃) ∈ Fin → ω ∈ Fin))
135, 12mtoi 199 . . . . . . . . 9 (𝑃 ∈ Fin → ¬ (ω ∖ 𝑃) ∈ Fin)
14 fin23lem.d . . . . . . . . . 10 𝑅 = (𝑤 ∈ ω ↦ (𝑥 ∈ (ω ∖ 𝑃)(𝑥 ∩ (ω ∖ 𝑃)) ≈ 𝑤))
1514fin23lem22 10396 . . . . . . . . 9 (((ω ∖ 𝑃) ⊆ ω ∧ ¬ (ω ∖ 𝑃) ∈ Fin) → 𝑅:ω–1-1-onto→(ω ∖ 𝑃))
164, 13, 15sylancr 586 . . . . . . . 8 (𝑃 ∈ Fin → 𝑅:ω–1-1-onto→(ω ∖ 𝑃))
1716adantl 481 . . . . . . 7 ((𝑡:ω–1-1→V ∧ 𝑃 ∈ Fin) → 𝑅:ω–1-1-onto→(ω ∖ 𝑃))
18 f1of1 6861 . . . . . . 7 (𝑅:ω–1-1-onto→(ω ∖ 𝑃) → 𝑅:ω–1-1→(ω ∖ 𝑃))
19 f1ss 6822 . . . . . . . 8 ((𝑅:ω–1-1→(ω ∖ 𝑃) ∧ (ω ∖ 𝑃) ⊆ ω) → 𝑅:ω–1-1→ω)
204, 19mpan2 690 . . . . . . 7 (𝑅:ω–1-1→(ω ∖ 𝑃) → 𝑅:ω–1-1→ω)
2117, 18, 203syl 18 . . . . . 6 ((𝑡:ω–1-1→V ∧ 𝑃 ∈ Fin) → 𝑅:ω–1-1→ω)
22 f1co 6828 . . . . . 6 ((𝑡:ω–1-1→V ∧ 𝑅:ω–1-1→ω) → (𝑡𝑅):ω–1-1→V)
2321, 22syldan 590 . . . . 5 ((𝑡:ω–1-1→V ∧ 𝑃 ∈ Fin) → (𝑡𝑅):ω–1-1→V)
24 f1eq1 6812 . . . . 5 (𝑍 = (𝑡𝑅) → (𝑍:ω–1-1→V ↔ (𝑡𝑅):ω–1-1→V))
2523, 24syl5ibrcom 247 . . . 4 ((𝑡:ω–1-1→V ∧ 𝑃 ∈ Fin) → (𝑍 = (𝑡𝑅) → 𝑍:ω–1-1→V))
2625impr 454 . . 3 ((𝑡:ω–1-1→V ∧ (𝑃 ∈ Fin ∧ 𝑍 = (𝑡𝑅))) → 𝑍:ω–1-1→V)
27 fvex 6933 . . . . . . . . . . 11 (𝑡𝑧) ∈ V
2827difexi 5348 . . . . . . . . . 10 ((𝑡𝑧) ∖ ran 𝑈) ∈ V
2928rgenw 3071 . . . . . . . . 9 𝑧𝑃 ((𝑡𝑧) ∖ ran 𝑈) ∈ V
30 eqid 2740 . . . . . . . . . 10 (𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) = (𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))
3130fmpt 7144 . . . . . . . . 9 (∀𝑧𝑃 ((𝑡𝑧) ∖ ran 𝑈) ∈ V ↔ (𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃⟶V)
3229, 31mpbi 230 . . . . . . . 8 (𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃⟶V
3332a1i 11 . . . . . . 7 (𝑡:ω–1-1→V → (𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃⟶V)
34 fveq2 6920 . . . . . . . . . . . . 13 (𝑧 = 𝑎 → (𝑡𝑧) = (𝑡𝑎))
3534difeq1d 4148 . . . . . . . . . . . 12 (𝑧 = 𝑎 → ((𝑡𝑧) ∖ ran 𝑈) = ((𝑡𝑎) ∖ ran 𝑈))
36 fvex 6933 . . . . . . . . . . . . 13 (𝑡𝑎) ∈ V
3736difexi 5348 . . . . . . . . . . . 12 ((𝑡𝑎) ∖ ran 𝑈) ∈ V
3835, 30, 37fvmpt 7029 . . . . . . . . . . 11 (𝑎𝑃 → ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑎) = ((𝑡𝑎) ∖ ran 𝑈))
3938ad2antrl 727 . . . . . . . . . 10 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑎) = ((𝑡𝑎) ∖ ran 𝑈))
40 fveq2 6920 . . . . . . . . . . . . 13 (𝑧 = 𝑏 → (𝑡𝑧) = (𝑡𝑏))
4140difeq1d 4148 . . . . . . . . . . . 12 (𝑧 = 𝑏 → ((𝑡𝑧) ∖ ran 𝑈) = ((𝑡𝑏) ∖ ran 𝑈))
42 fvex 6933 . . . . . . . . . . . . 13 (𝑡𝑏) ∈ V
4342difexi 5348 . . . . . . . . . . . 12 ((𝑡𝑏) ∖ ran 𝑈) ∈ V
4441, 30, 43fvmpt 7029 . . . . . . . . . . 11 (𝑏𝑃 → ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑏) = ((𝑡𝑏) ∖ ran 𝑈))
4544ad2antll 728 . . . . . . . . . 10 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑏) = ((𝑡𝑏) ∖ ran 𝑈))
4639, 45eqeq12d 2756 . . . . . . . . 9 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → (((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑎) = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑏) ↔ ((𝑡𝑎) ∖ ran 𝑈) = ((𝑡𝑏) ∖ ran 𝑈)))
47 uneq2 4185 . . . . . . . . . . 11 (((𝑡𝑎) ∖ ran 𝑈) = ((𝑡𝑏) ∖ ran 𝑈) → ( ran 𝑈 ∪ ((𝑡𝑎) ∖ ran 𝑈)) = ( ran 𝑈 ∪ ((𝑡𝑏) ∖ ran 𝑈)))
48 fveq2 6920 . . . . . . . . . . . . . . . . 17 (𝑣 = 𝑎 → (𝑡𝑣) = (𝑡𝑎))
4948sseq2d 4041 . . . . . . . . . . . . . . . 16 (𝑣 = 𝑎 → ( ran 𝑈 ⊆ (𝑡𝑣) ↔ ran 𝑈 ⊆ (𝑡𝑎)))
5049, 6elrab2 3711 . . . . . . . . . . . . . . 15 (𝑎𝑃 ↔ (𝑎 ∈ ω ∧ ran 𝑈 ⊆ (𝑡𝑎)))
5150simprbi 496 . . . . . . . . . . . . . 14 (𝑎𝑃 ran 𝑈 ⊆ (𝑡𝑎))
5251ad2antrl 727 . . . . . . . . . . . . 13 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ran 𝑈 ⊆ (𝑡𝑎))
53 undif 4505 . . . . . . . . . . . . 13 ( ran 𝑈 ⊆ (𝑡𝑎) ↔ ( ran 𝑈 ∪ ((𝑡𝑎) ∖ ran 𝑈)) = (𝑡𝑎))
5452, 53sylib 218 . . . . . . . . . . . 12 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ( ran 𝑈 ∪ ((𝑡𝑎) ∖ ran 𝑈)) = (𝑡𝑎))
55 fveq2 6920 . . . . . . . . . . . . . . . . 17 (𝑣 = 𝑏 → (𝑡𝑣) = (𝑡𝑏))
5655sseq2d 4041 . . . . . . . . . . . . . . . 16 (𝑣 = 𝑏 → ( ran 𝑈 ⊆ (𝑡𝑣) ↔ ran 𝑈 ⊆ (𝑡𝑏)))
5756, 6elrab2 3711 . . . . . . . . . . . . . . 15 (𝑏𝑃 ↔ (𝑏 ∈ ω ∧ ran 𝑈 ⊆ (𝑡𝑏)))
5857simprbi 496 . . . . . . . . . . . . . 14 (𝑏𝑃 ran 𝑈 ⊆ (𝑡𝑏))
5958ad2antll 728 . . . . . . . . . . . . 13 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ran 𝑈 ⊆ (𝑡𝑏))
60 undif 4505 . . . . . . . . . . . . 13 ( ran 𝑈 ⊆ (𝑡𝑏) ↔ ( ran 𝑈 ∪ ((𝑡𝑏) ∖ ran 𝑈)) = (𝑡𝑏))
6159, 60sylib 218 . . . . . . . . . . . 12 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ( ran 𝑈 ∪ ((𝑡𝑏) ∖ ran 𝑈)) = (𝑡𝑏))
6254, 61eqeq12d 2756 . . . . . . . . . . 11 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → (( ran 𝑈 ∪ ((𝑡𝑎) ∖ ran 𝑈)) = ( ran 𝑈 ∪ ((𝑡𝑏) ∖ ran 𝑈)) ↔ (𝑡𝑎) = (𝑡𝑏)))
6347, 62imbitrid 244 . . . . . . . . . 10 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → (((𝑡𝑎) ∖ ran 𝑈) = ((𝑡𝑏) ∖ ran 𝑈) → (𝑡𝑎) = (𝑡𝑏)))
647sseli 4004 . . . . . . . . . . . 12 (𝑎𝑃𝑎 ∈ ω)
657sseli 4004 . . . . . . . . . . . 12 (𝑏𝑃𝑏 ∈ ω)
6664, 65anim12i 612 . . . . . . . . . . 11 ((𝑎𝑃𝑏𝑃) → (𝑎 ∈ ω ∧ 𝑏 ∈ ω))
67 f1fveq 7299 . . . . . . . . . . 11 ((𝑡:ω–1-1→V ∧ (𝑎 ∈ ω ∧ 𝑏 ∈ ω)) → ((𝑡𝑎) = (𝑡𝑏) ↔ 𝑎 = 𝑏))
6866, 67sylan2 592 . . . . . . . . . 10 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → ((𝑡𝑎) = (𝑡𝑏) ↔ 𝑎 = 𝑏))
6963, 68sylibd 239 . . . . . . . . 9 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → (((𝑡𝑎) ∖ ran 𝑈) = ((𝑡𝑏) ∖ ran 𝑈) → 𝑎 = 𝑏))
7046, 69sylbid 240 . . . . . . . 8 ((𝑡:ω–1-1→V ∧ (𝑎𝑃𝑏𝑃)) → (((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑎) = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑏) → 𝑎 = 𝑏))
7170ralrimivva 3208 . . . . . . 7 (𝑡:ω–1-1→V → ∀𝑎𝑃𝑏𝑃 (((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑎) = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑏) → 𝑎 = 𝑏))
72 dff13 7292 . . . . . . 7 ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃1-1→V ↔ ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃⟶V ∧ ∀𝑎𝑃𝑏𝑃 (((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑎) = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈))‘𝑏) → 𝑎 = 𝑏)))
7333, 71, 72sylanbrc 582 . . . . . 6 (𝑡:ω–1-1→V → (𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃1-1→V)
74 fin23lem.c . . . . . . . . 9 𝑄 = (𝑤 ∈ ω ↦ (𝑥𝑃 (𝑥𝑃) ≈ 𝑤))
7574fin23lem22 10396 . . . . . . . 8 ((𝑃 ⊆ ω ∧ ¬ 𝑃 ∈ Fin) → 𝑄:ω–1-1-onto𝑃)
76 f1of1 6861 . . . . . . . 8 (𝑄:ω–1-1-onto𝑃𝑄:ω–1-1𝑃)
7775, 76syl 17 . . . . . . 7 ((𝑃 ⊆ ω ∧ ¬ 𝑃 ∈ Fin) → 𝑄:ω–1-1𝑃)
787, 77mpan 689 . . . . . 6 𝑃 ∈ Fin → 𝑄:ω–1-1𝑃)
79 f1co 6828 . . . . . 6 (((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)):𝑃1-1→V ∧ 𝑄:ω–1-1𝑃) → ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄):ω–1-1→V)
8073, 78, 79syl2an 595 . . . . 5 ((𝑡:ω–1-1→V ∧ ¬ 𝑃 ∈ Fin) → ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄):ω–1-1→V)
81 f1eq1 6812 . . . . 5 (𝑍 = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄) → (𝑍:ω–1-1→V ↔ ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄):ω–1-1→V))
8280, 81syl5ibrcom 247 . . . 4 ((𝑡:ω–1-1→V ∧ ¬ 𝑃 ∈ Fin) → (𝑍 = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄) → 𝑍:ω–1-1→V))
8382impr 454 . . 3 ((𝑡:ω–1-1→V ∧ (¬ 𝑃 ∈ Fin ∧ 𝑍 = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄))) → 𝑍:ω–1-1→V)
8426, 83jaodan 958 . 2 ((𝑡:ω–1-1→V ∧ ((𝑃 ∈ Fin ∧ 𝑍 = (𝑡𝑅)) ∨ (¬ 𝑃 ∈ Fin ∧ 𝑍 = ((𝑧𝑃 ↦ ((𝑡𝑧) ∖ ran 𝑈)) ∘ 𝑄)))) → 𝑍:ω–1-1→V)
853, 84mpan2 690 1 (𝑡:ω–1-1→V → 𝑍:ω–1-1→V)
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wb 206  wa 395  wo 846   = wceq 1537  wcel 2108  {cab 2717  wral 3067  {crab 3443  Vcvv 3488  cdif 3973  cun 3974  cin 3975  wss 3976  c0 4352  ifcif 4548  𝒫 cpw 4622   cuni 4931   cint 4970   class class class wbr 5166  cmpt 5249  ran crn 5701  ccom 5704  suc csuc 6397  wf 6569  1-1wf1 6570  1-1-ontowf1o 6572  cfv 6573  crio 7403  (class class class)co 7448  cmpo 7450  ωcom 7903  seqωcseqom 8503  m cmap 8884  cen 9000  Fincfn 9003
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1793  ax-4 1807  ax-5 1909  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-10 2141  ax-11 2158  ax-12 2178  ax-ext 2711  ax-rep 5303  ax-sep 5317  ax-nul 5324  ax-pow 5383  ax-pr 5447  ax-un 7770
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 847  df-3or 1088  df-3an 1089  df-tru 1540  df-fal 1550  df-ex 1778  df-nf 1782  df-sb 2065  df-mo 2543  df-eu 2572  df-clab 2718  df-cleq 2732  df-clel 2819  df-nfc 2895  df-ne 2947  df-ral 3068  df-rex 3077  df-rmo 3388  df-reu 3389  df-rab 3444  df-v 3490  df-sbc 3805  df-csb 3922  df-dif 3979  df-un 3981  df-in 3983  df-ss 3993  df-pss 3996  df-nul 4353  df-if 4549  df-pw 4624  df-sn 4649  df-pr 4651  df-op 4655  df-uni 4932  df-int 4971  df-iun 5017  df-br 5167  df-opab 5229  df-mpt 5250  df-tr 5284  df-id 5593  df-eprel 5599  df-po 5607  df-so 5608  df-fr 5652  df-se 5653  df-we 5654  df-xp 5706  df-rel 5707  df-cnv 5708  df-co 5709  df-dm 5710  df-rn 5711  df-res 5712  df-ima 5713  df-pred 6332  df-ord 6398  df-on 6399  df-lim 6400  df-suc 6401  df-iota 6525  df-fun 6575  df-fn 6576  df-f 6577  df-f1 6578  df-fo 6579  df-f1o 6580  df-fv 6581  df-isom 6582  df-riota 7404  df-ov 7451  df-om 7904  df-2nd 8031  df-frecs 8322  df-wrecs 8353  df-recs 8427  df-1o 8522  df-er 8763  df-en 9004  df-dom 9005  df-sdom 9006  df-fin 9007  df-card 10008
This theorem is referenced by:  fin23lem32  10413
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