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Theorem reuccats1 13526
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 2713 . . . 4 (𝑥 = 𝑦 → (𝑥 ∈ Word 𝑉𝑦 ∈ Word 𝑉))
2 fveq2 6229 . . . . 5 (𝑥 = 𝑦 → (#‘𝑥) = (#‘𝑦))
32eqeq1d 2653 . . . 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 3201 . 2 (∀𝑥𝑋 (𝑥 ∈ Word 𝑉 ∧ (#‘𝑥) = ((#‘𝑊) + 1)) ↔ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1)))
6 reuccats1.1 . . . . 5 𝑣𝑋
76nfel2 2810 . . . 4 𝑣(𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋
86nfel2 2810 . . . 4 𝑣(𝑊 ++ ⟨“𝑥”⟩) ∈ 𝑋
9 s1eq 13416 . . . . . 6 (𝑣 = 𝑥 → ⟨“𝑣”⟩ = ⟨“𝑥”⟩)
109oveq2d 6706 . . . . 5 (𝑣 = 𝑥 → (𝑊 ++ ⟨“𝑣”⟩) = (𝑊 ++ ⟨“𝑥”⟩))
1110eleq1d 2715 . . . 4 (𝑣 = 𝑥 → ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ↔ (𝑊 ++ ⟨“𝑥”⟩) ∈ 𝑋))
12 s1eq 13416 . . . . . 6 (𝑥 = 𝑢 → ⟨“𝑥”⟩ = ⟨“𝑢”⟩)
1312oveq2d 6706 . . . . 5 (𝑥 = 𝑢 → (𝑊 ++ ⟨“𝑥”⟩) = (𝑊 ++ ⟨“𝑢”⟩))
1413eleq1d 2715 . . . 4 (𝑥 = 𝑢 → ((𝑊 ++ ⟨“𝑥”⟩) ∈ 𝑋 ↔ (𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋))
157, 8, 11, 14reu8nf 3549 . . 3 (∃!𝑣𝑉 (𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ↔ ∃𝑣𝑉 ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢)))
16 nfv 1883 . . . . 5 𝑣 𝑊 ∈ Word 𝑉
17 nfv 1883 . . . . . 6 𝑣(𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))
186, 17nfral 2974 . . . . 5 𝑣𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))
1916, 18nfan 1868 . . . 4 𝑣(𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1)))
20 nfv 1883 . . . . 5 𝑣 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)
216, 20nfreu 3143 . . . 4 𝑣∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩)
22 simprl 809 . . . . . 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 823 . . . . . . . . 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 476 . . . . . . . . 9 (((((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) ∧ ((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑢𝑉 ((𝑊 ++ ⟨“𝑢”⟩) ∈ 𝑋𝑣 = 𝑢))) ∧ 𝑥𝑋) → 𝑥𝑋)
2522adantr 480 . . . . . . . . 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 818 . . . . . . . . 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 824 . . . . . . . . 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 13525 . . . . . . . . 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 1374 . . . . . . . 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 6697 . . . . . . . . . . 11 (𝑥 = (𝑊 ++ ⟨“𝑣”⟩) → (𝑥 substr ⟨0, (#‘𝑊)⟩) = ((𝑊 ++ ⟨“𝑣”⟩) substr ⟨0, (#‘𝑊)⟩))
31 simpl 472 . . . . . . . . . . . . . . 15 ((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) → 𝑊 ∈ Word 𝑉)
32 s1cl 13418 . . . . . . . . . . . . . . 15 (𝑣𝑉 → ⟨“𝑣”⟩ ∈ Word 𝑉)
3331, 32anim12i 589 . . . . . . . . . . . . . 14 (((𝑊 ∈ Word 𝑉 ∧ ∀𝑦𝑋 (𝑦 ∈ Word 𝑉 ∧ (#‘𝑦) = ((#‘𝑊) + 1))) ∧ 𝑣𝑉) → (𝑊 ∈ Word 𝑉 ∧ ⟨“𝑣”⟩ ∈ Word 𝑉))
3433adantr 480 . . . . . . . . . . . . 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 480 . . . . . . . . . . . 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 13503 . . . . . . . . . . . 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 2707 . . . . . . . . . 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 2657 . . . . . . . . 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 449 . . . . . . . 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 2995 . . . . . 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 3430 . . . . . 6 (((𝑊 ++ ⟨“𝑣”⟩) ∈ 𝑋 ∧ ∀𝑥𝑋 (𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩) ↔ 𝑥 = (𝑊 ++ ⟨“𝑣”⟩))) → ∃!𝑥𝑋 𝑊 = (𝑥 substr ⟨0, (#‘𝑊)⟩))
4422, 42, 43syl2anc 694 . . . . 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 629 . . . 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 3055 . . 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 491 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 383   = wceq 1523  wcel 2030  wnfc 2780  wral 2941  wrex 2942  ∃!wreu 2943  cop 4216  cfv 5926  (class class class)co 6690  0cc0 9974  1c1 9975   + caddc 9977  #chash 13157  Word cword 13323   ++ cconcat 13325  ⟨“cs1 13326   substr csubstr 13327
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1762  ax-4 1777  ax-5 1879  ax-6 1945  ax-7 1981  ax-8 2032  ax-9 2039  ax-10 2059  ax-11 2074  ax-12 2087  ax-13 2282  ax-ext 2631  ax-rep 4804  ax-sep 4814  ax-nul 4822  ax-pow 4873  ax-pr 4936  ax-un 6991  ax-cnex 10030  ax-resscn 10031  ax-1cn 10032  ax-icn 10033  ax-addcl 10034  ax-addrcl 10035  ax-mulcl 10036  ax-mulrcl 10037  ax-mulcom 10038  ax-addass 10039  ax-mulass 10040  ax-distr 10041  ax-i2m1 10042  ax-1ne0 10043  ax-1rid 10044  ax-rnegex 10045  ax-rrecex 10046  ax-cnre 10047  ax-pre-lttri 10048  ax-pre-lttrn 10049  ax-pre-ltadd 10050  ax-pre-mulgt0 10051
This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3or 1055  df-3an 1056  df-tru 1526  df-ex 1745  df-nf 1750  df-sb 1938  df-eu 2502  df-mo 2503  df-clab 2638  df-cleq 2644  df-clel 2647  df-nfc 2782  df-ne 2824  df-nel 2927  df-ral 2946  df-rex 2947  df-reu 2948  df-rab 2950  df-v 3233  df-sbc 3469  df-csb 3567  df-dif 3610  df-un 3612  df-in 3614  df-ss 3621  df-pss 3623  df-nul 3949  df-if 4120  df-pw 4193  df-sn 4211  df-pr 4213  df-tp 4215  df-op 4217  df-uni 4469  df-int 4508  df-iun 4554  df-br 4686  df-opab 4746  df-mpt 4763  df-tr 4786  df-id 5053  df-eprel 5058  df-po 5064  df-so 5065  df-fr 5102  df-we 5104  df-xp 5149  df-rel 5150  df-cnv 5151  df-co 5152  df-dm 5153  df-rn 5154  df-res 5155  df-ima 5156  df-pred 5718  df-ord 5764  df-on 5765  df-lim 5766  df-suc 5767  df-iota 5889  df-fun 5928  df-fn 5929  df-f 5930  df-f1 5931  df-fo 5932  df-f1o 5933  df-fv 5934  df-riota 6651  df-ov 6693  df-oprab 6694  df-mpt2 6695  df-om 7108  df-1st 7210  df-2nd 7211  df-wrecs 7452  df-recs 7513  df-rdg 7551  df-1o 7605  df-oadd 7609  df-er 7787  df-en 7998  df-dom 7999  df-sdom 8000  df-fin 8001  df-card 8803  df-pnf 10114  df-mnf 10115  df-xr 10116  df-ltxr 10117  df-le 10118  df-sub 10306  df-neg 10307  df-nn 11059  df-n0 11331  df-xnn0 11402  df-z 11416  df-uz 11726  df-fz 12365  df-fzo 12505  df-hash 13158  df-word 13331  df-lsw 13332  df-concat 13333  df-s1 13334  df-substr 13335
This theorem is referenced by:  reuccats1v  13527  numclwlk2lem2f1o  27359  numclwlk2lem2f1oOLD  27366
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