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Theorem reuccats1 13480
Description: A set of words having the length of a given word increased by 1 contains a unique word with the given word as prefix if there is a unique symbol which extends the given word to be a word of the set. (Contributed by Alexander van der Vekens, 6-Oct-2018.) (Revised by AV, 21-Jan-2022.)
Hypothesis
Ref Expression
reuccats1.1 𝑣𝑋
Assertion
Ref Expression
reuccats1 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑥𝑋 (𝑥 ∈ Word 𝑉 ∧ (#‘𝑥) = ((#‘𝑊) + 1))) → (∃!𝑣𝑉 (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)))
Distinct variable groups:   𝑣,𝑉,𝑥   𝑣,𝑊,𝑥   𝑥,𝑋
Allowed substitution hint:   𝑋(𝑣)

Proof of Theorem reuccats1
Dummy variables 𝑢 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eleq1w 2684 . . . 4 (𝑥 = 𝑦 → (𝑥 ∈ Word 𝑉𝑦 ∈ Word 𝑉))
2 fveq2 6191 . . . . 5 (𝑥 = 𝑦 → (#‘𝑥) = (#‘𝑦))
32eqeq1d 2624 . . . 4 (𝑥 = 𝑦 → ((#‘𝑥) = ((#‘𝑊) + 1) ↔ (#‘𝑦) = ((#‘𝑊) + 1)))
41, 3anbi12d 747 . . 3 (𝑥 = 𝑦 → ((𝑥 ∈ Word 𝑉 ∧ (#‘𝑥) = ((#‘𝑊) + 1)) ↔ (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))))
54cbvralv 3171 . 2 (∀𝑥𝑋 (𝑥 ∈ Word 𝑉 ∧ (#‘𝑥) = ((#‘𝑊) + 1)) ↔ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1)))
6 reuccats1.1 . . . . 5 𝑣𝑋
76nfel2 2781 . . . 4 𝑣(𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋
86nfel2 2781 . . . 4 𝑣(𝑊 ++ ⟨“𝑥”⟩) ∈ 𝑋
9 s1eq 13380 . . . . . 6 (𝑣 = 𝑥 → ⟨“𝑣”⟩ = ⟨“𝑥”⟩)
109oveq2d 6666 . . . . 5 (𝑣 = 𝑥 → (𝑊 ++ ⟨“𝑣”⟩) = (𝑊 ++ ⟨“𝑥”⟩))
1110eleq1d 2686 . . . 4 (𝑣 = 𝑥 → ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ↔ (𝑊 ++ ⟨“𝑥”⟩) ∈ 𝑋))
12 s1eq 13380 . . . . . 6 (𝑥 = 𝑢 → ⟨“𝑥”⟩ = ⟨“𝑢”⟩)
1312oveq2d 6666 . . . . 5 (𝑥 = 𝑢 → (𝑊 ++ ⟨“𝑥”⟩) = (𝑊 ++ ⟨“𝑢”⟩))
1413eleq1d 2686 . . . 4 (𝑥 = 𝑢 → ((𝑊 ++ ⟨“𝑥”⟩) ∈ 𝑋 ↔ (𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋))
157, 8, 11, 14reu8nf 3516 . . 3 (∃!𝑣𝑉 (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ↔ ∃𝑣𝑉 ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢)))
16 nfv 1843 . . . . 5 𝑣 𝑊 ∈ Word 𝑉
17 nfv 1843 . . . . . 6 𝑣(𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))
186, 17nfral 2945 . . . . 5 𝑣𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))
1916, 18nfan 1828 . . . 4 𝑣(𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1)))
20 nfv 1843 . . . . 5 𝑣 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)
216, 20nfreu 3114 . . . 4 𝑣∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)
22 simprl 794 . . . . . 6 ((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) → (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋)
23 simp-4l 806 . . . . . . . . 9 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → 𝑊 ∈ Word 𝑉)
24 simpr 477 . . . . . . . . 9 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → 𝑥𝑋)
2522adantr 481 . . . . . . . . 9 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋)
26 simplrr 801 . . . . . . . . 9 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))
27 simp-4r 807 . . . . . . . . 9 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1)))
28 reuccats1lem 13479 . . . . . . . . 9 (((𝑊 ∈ Word 𝑉𝑥𝑋 ∧ (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋) ∧ (∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢) ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1)))) → (𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩) → 𝑥 = (𝑊 ++ ⟨“𝑣”⟩)))
2923, 24, 25, 26, 27, 28syl32anc 1334 . . . . . . . 8 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → (𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩) → 𝑥 = (𝑊 ++ ⟨“𝑣”⟩)))
30 oveq1 6657 . . . . . . . . . . 11 (𝑥 = (𝑊 ++ ⟨“𝑣”⟩) → (𝑥 substr ⟨0, (#‘𝑊)⟩) = ((𝑊 ++ ⟨“𝑣”⟩) substr ⟨0, (#‘𝑊)⟩))
31 simpl 473 . . . . . . . . . . . . . . 15 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) → 𝑊 ∈ Word 𝑉)
32 s1cl 13382 . . . . . . . . . . . . . . 15 (𝑣𝑉 → ⟨“𝑣”⟩ ∈ Word 𝑉)
3331, 32anim12i 590 . . . . . . . . . . . . . 14 (((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) → (𝑊 ∈ Word 𝑉 ∧ ⟨“𝑣”⟩ ∈ Word 𝑉))
3433adantr 481 . . . . . . . . . . . . 13 ((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) → (𝑊 ∈ Word 𝑉 ∧ ⟨“𝑣”⟩ ∈ Word 𝑉))
3534adantr 481 . . . . . . . . . . . 12 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → (𝑊 ∈ Word 𝑉 ∧ ⟨“𝑣”⟩ ∈ Word 𝑉))
36 swrdccat1 13457 . . . . . . . . . . . 12 ((𝑊 ∈ Word 𝑉 ∧ ⟨“𝑣”⟩ ∈ Word 𝑉) → ((𝑊 ++ ⟨“𝑣”⟩) substr ⟨0, (#‘𝑊)⟩) = 𝑊)
3735, 36syl 17 . . . . . . . . . . 11 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → ((𝑊 ++ ⟨“𝑣”⟩) substr ⟨0, (#‘𝑊)⟩) = 𝑊)
3830, 37sylan9eqr 2678 . . . . . . . . . 10 ((((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) ∧ 𝑥 = (𝑊 ++ ⟨“𝑣”⟩)) → (𝑥 substr ⟨0, (#‘𝑊)⟩) = 𝑊)
3938eqcomd 2628 . . . . . . . . 9 ((((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) ∧ 𝑥 = (𝑊 ++ ⟨“𝑣”⟩)) → 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩))
4039ex 450 . . . . . . . 8 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → (𝑥 = (𝑊 ++ ⟨“𝑣”⟩) → 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)))
4129, 40impbid 202 . . . . . . 7 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → (𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩) ↔ 𝑥 = (𝑊 ++ ⟨“𝑣”⟩)))
4241ralrimiva 2966 . . . . . 6 ((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) → ∀𝑥𝑋 (𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩) ↔ 𝑥 = (𝑊 ++ ⟨“𝑣”⟩)))
43 reu6i 3397 . . . . . 6 (((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑥𝑋 (𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩) ↔ 𝑥 = (𝑊 ++ ⟨“𝑣”⟩))) → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩))
4422, 42, 43syl2anc 693 . . . . 5 ((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩))
4544exp31 630 . . . 4 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) → (𝑣𝑉 → (((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢)) → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩))))
4619, 21, 45rexlimd 3026 . . 3 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) → (∃𝑣𝑉 ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢)) → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)))
4715, 46syl5bi 232 . 2 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) → (∃!𝑣𝑉 (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)))
485, 47sylan2b 492 1 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑥𝑋 (𝑥 ∈ Word 𝑉 ∧ (#‘𝑥) = ((#‘𝑊) + 1))) → (∃!𝑣𝑉 (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 196  wa 384   = wceq 1483  wcel 1990  wnfc 2751  wral 2912  wrex 2913  ∃!wreu 2914  cop 4183  cfv 5888  (class class class)co 6650  0cc0 9936  1c1 9937   + caddc 9939  #chash 13117  Word cword 13291   ++ cconcat 13293  ⟨“cs1 13294   substr csubstr 13295
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-cnex 9992  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012  ax-pre-mulgt0 10013
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-int 4476  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-pred 5680  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-om 7066  df-1st 7168  df-2nd 7169  df-wrecs 7407  df-recs 7468  df-rdg 7506  df-1o 7560  df-oadd 7564  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-fin 7959  df-card 8765  df-pnf 10076  df-mnf 10077  df-xr 10078  df-ltxr 10079  df-le 10080  df-sub 10268  df-neg 10269  df-nn 11021  df-n0 11293  df-xnn0 11364  df-z 11378  df-uz 11688  df-fz 12327  df-fzo 12466  df-hash 13118  df-word 13299  df-lsw 13300  df-concat 13301  df-s1 13302  df-substr 13303
This theorem is referenced by:  reuccats1v  13481  numclwlk2lem2f1o  27238
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