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Theorem hlimunii 5143
Description: A Hilbert space sequence converges to at most one limit.
Hypotheses
Ref Expression
hlimuni.1 AV
hlimuni.2 BV
hlimuni.3 FV
hlimunii.3 (Fv AFv B)
Assertion
Ref Expression
hlimunii A = B

Proof of Theorem hlimunii
StepHypRef Expression
1 nn2get 4438 . . . . 5 ((y ∈ ℕ ∧ w ∈ ℕ) → ∃z ∈ ℕ (yzwz))
21rgen2 1248 . . . 4 y ∈ ℕ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz)
3 hlimunii.3 . . . . . . . . . 10 (Fv AFv B)
43pm3.26i 257 . . . . . . . . 9 Fv A
5 hlimuni.3 . . . . . . . . . 10 FV
6 hlimuni.1 . . . . . . . . . 10 AV
75, 6hlimvec 5110 . . . . . . . . 9 (Fv AA ∈ ℋ )
84, 7ax-mp 6 . . . . . . . 8 A ∈ ℋ
93pm3.27i 261 . . . . . . . . 9 Fv B
10 hlimuni.2 . . . . . . . . . 10 BV
115, 10hlimvec 5110 . . . . . . . . 9 (Fv BB ∈ ℋ )
129, 11ax-mp 6 . . . . . . . 8 B ∈ ℋ
138, 12hvsubcl 5002 . . . . . . 7 (Av B) ∈ ℋ
1413normcl 5081 . . . . . 6 (norm ‘(Av B)) ∈ ℝ
15 2re 4470 . . . . . 6 2 ∈ ℝ
16 2pos 4479 . . . . . 6 0 < 2
1714, 15, 16divgt0lem 4389 . . . . 5 (0 < (norm ‘(Av B)) → 0 < ((norm ‘(Av B)) / 2))
185, 6hlimconv 5111 . . . . . . . 8 (Fv A → ∀x ∈ ℝ (0 < x → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < x)))
194, 18ax-mp 6 . . . . . . 7 x ∈ ℝ (0 < x → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < x))
2015, 16gt0ne0i 4345 . . . . . . . 8 2 ≠ 0
2114, 15, 20redivcl 4274 . . . . . . 7 ((norm ‘(Av B)) / 2) ∈ ℝ
22 breq2 2066 . . . . . . . . 9 (x = ((norm ‘(Av B)) / 2) → (0 < x ↔ 0 < ((norm ‘(Av B)) / 2)))
23 breq2 2066 . . . . . . . . . . . 12 (x = ((norm ‘(Av B)) / 2) → ((norm ‘((Fz) −v A)) < x ↔ (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)))
2423imbi2d 464 . . . . . . . . . . 11 (x = ((norm ‘(Av B)) / 2) → ((yz → (norm ‘((Fz) −v A)) < x) ↔ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2))))
2524biraldv 1219 . . . . . . . . . 10 (x = ((norm ‘(Av B)) / 2) → (∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < x) ↔ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2))))
2625birexdv 1220 . . . . . . . . 9 (x = ((norm ‘(Av B)) / 2) → (∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < x) ↔ ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2))))
2722, 26imbi12d 474 . . . . . . . 8 (x = ((norm ‘(Av B)) / 2) → ((0 < x → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < x)) ↔ (0 < ((norm ‘(Av B)) / 2) → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)))))
2827rcla4v 1402 . . . . . . 7 (∀x ∈ ℝ (0 < x → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < x)) → (((norm ‘(Av B)) / 2) ∈ ℝ → (0 < ((norm ‘(Av B)) / 2) → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)))))
2919, 21, 28mp2 43 . . . . . 6 (0 < ((norm ‘(Av B)) / 2) → ∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)))
305, 10hlimconv 5111 . . . . . . . 8 (Fv B → ∀x ∈ ℝ (0 < x → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < x)))
319, 30ax-mp 6 . . . . . . 7 x ∈ ℝ (0 < x → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < x))
32 breq2 2066 . . . . . . . . . . . 12 (x = ((norm ‘(Av B)) / 2) → ((norm ‘((Fz) −v B)) < x ↔ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)))
3332imbi2d 464 . . . . . . . . . . 11 (x = ((norm ‘(Av B)) / 2) → ((wz → (norm ‘((Fz) −v B)) < x) ↔ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
3433biraldv 1219 . . . . . . . . . 10 (x = ((norm ‘(Av B)) / 2) → (∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < x) ↔ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
3534birexdv 1220 . . . . . . . . 9 (x = ((norm ‘(Av B)) / 2) → (∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < x) ↔ ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
3622, 35imbi12d 474 . . . . . . . 8 (x = ((norm ‘(Av B)) / 2) → ((0 < x → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < x)) ↔ (0 < ((norm ‘(Av B)) / 2) → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)))))
3736rcla4v 1402 . . . . . . 7 (∀x ∈ ℝ (0 < x → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < x)) → (((norm ‘(Av B)) / 2) ∈ ℝ → (0 < ((norm ‘(Av B)) / 2) → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)))))
3831, 21, 37mp2 43 . . . . . 6 (0 < ((norm ‘(Av B)) / 2) → ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)))
3929, 38jca 236 . . . . 5 (0 < ((norm ‘(Av B)) / 2) → (∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
40 r19.26 1289 . . . . . . . . 9 (∀z ∈ ℕ ((yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) ↔ (∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
4114ltnr 4338 . . . . . . . . . . . . 13 ¬ (norm ‘(Av B)) < (norm ‘(Av B))
425, 6hlimseq 5109 . . . . . . . . . . . . . . . . . . 19 (Fv AF:ℕ–→ ℋ )
434, 42ax-mp 6 . . . . . . . . . . . . . . . . . 18 F:ℕ–→ ℋ
44 ffvrn 2890 . . . . . . . . . . . . . . . . . 18 ((F:ℕ–→ ℋ ∧ z ∈ ℕ) → (Fz) ∈ ℋ )
4543, 44mpan 518 . . . . . . . . . . . . . . . . 17 (z ∈ ℕ → (Fz) ∈ ℋ )
46 normsubt 5091 . . . . . . . . . . . . . . . . . 18 (((Fz) ∈ ℋ ∧ A ∈ ℋ ) → (norm ‘((Fz) −v A)) = (norm ‘(Av (Fz))))
478, 46mpan2 519 . . . . . . . . . . . . . . . . 17 ((Fz) ∈ ℋ → (norm ‘((Fz) −v A)) = (norm ‘(Av (Fz))))
4845, 47syl 12 . . . . . . . . . . . . . . . 16 (z ∈ ℕ → (norm ‘((Fz) −v A)) = (norm ‘(Av (Fz))))
4948breq1d 2071 . . . . . . . . . . . . . . 15 (z ∈ ℕ → ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ↔ (norm ‘(Av (Fz))) < ((norm ‘(Av B)) / 2)))
5049anbi1d 469 . . . . . . . . . . . . . 14 (z ∈ ℕ → (((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) ↔ ((norm ‘(Av (Fz))) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
518, 12pm3.2i 234 . . . . . . . . . . . . . . . . 17 (A ∈ ℋ ∧ B ∈ ℋ )
52 norm3lemt 5097 . . . . . . . . . . . . . . . . 17 (((A ∈ ℋ ∧ B ∈ ℋ ) ∧ ((Fz) ∈ ℋ ∧ (norm ‘(Av B)) ∈ ℝ)) → (((norm ‘(Av (Fz))) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → (norm ‘(Av B)) < (norm ‘(Av B))))
5351, 52mpan 518 . . . . . . . . . . . . . . . 16 (((Fz) ∈ ℋ ∧ (norm ‘(Av B)) ∈ ℝ) → (((norm ‘(Av (Fz))) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → (norm ‘(Av B)) < (norm ‘(Av B))))
5414, 53mpan2 519 . . . . . . . . . . . . . . 15 ((Fz) ∈ ℋ → (((norm ‘(Av (Fz))) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → (norm ‘(Av B)) < (norm ‘(Av B))))
5545, 54syl 12 . . . . . . . . . . . . . 14 (z ∈ ℕ → (((norm ‘(Av (Fz))) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → (norm ‘(Av B)) < (norm ‘(Av B))))
5650, 55sylbid 178 . . . . . . . . . . . . 13 (z ∈ ℕ → (((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → (norm ‘(Av B)) < (norm ‘(Av B))))
5741, 56mtoi 94 . . . . . . . . . . . 12 (z ∈ ℕ → ¬ ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)))
58 con3 86 . . . . . . . . . . . . 13 (((yzwz) → ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → (¬ ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → ¬ (yzwz)))
5958com12 13 . . . . . . . . . . . 12 (¬ ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2)) → (((yzwz) → ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ¬ (yzwz)))
6057, 59syl 12 . . . . . . . . . . 11 (z ∈ ℕ → (((yzwz) → ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ¬ (yzwz)))
61 prth 429 . . . . . . . . . . 11 (((yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ((yzwz) → ((norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2) ∧ (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
6260, 61syl5 22 . . . . . . . . . 10 (z ∈ ℕ → (((yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ¬ (yzwz)))
6362r19.20i 1253 . . . . . . . . 9 (∀z ∈ ℕ ((yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ∀z ∈ ℕ ¬ (yzwz))
6440, 63sylbir 176 . . . . . . . 8 ((∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ∀z ∈ ℕ ¬ (yzwz))
6564r19.22si 1275 . . . . . . 7 (∃w ∈ ℕ (∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ∃w ∈ ℕ ∀z ∈ ℕ ¬ (yzwz))
6665r19.22si 1275 . . . . . 6 (∃y ∈ ℕ ∃w ∈ ℕ (∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ∃y ∈ ℕ ∃w ∈ ℕ ∀z ∈ ℕ ¬ (yzwz))
67 reeanv 1316 . . . . . 6 (∃y ∈ ℕ ∃w ∈ ℕ (∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) ↔ (∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))))
68 ralnex 1209 . . . . . . . . . 10 (∀z ∈ ℕ ¬ (yzwz) ↔ ¬ ∃z ∈ ℕ (yzwz))
6968birex 1224 . . . . . . . . 9 (∃w ∈ ℕ ∀z ∈ ℕ ¬ (yzwz) ↔ ∃w ∈ ℕ ¬ ∃z ∈ ℕ (yzwz))
70 rexnal 1210 . . . . . . . . 9 (∃w ∈ ℕ ¬ ∃z ∈ ℕ (yzwz) ↔ ¬ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
7169, 70bitr 151 . . . . . . . 8 (∃w ∈ ℕ ∀z ∈ ℕ ¬ (yzwz) ↔ ¬ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
7271birex 1224 . . . . . . 7 (∃y ∈ ℕ ∃w ∈ ℕ ∀z ∈ ℕ ¬ (yzwz) ↔ ∃y ∈ ℕ ¬ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
73 rexnal 1210 . . . . . . 7 (∃y ∈ ℕ ¬ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz) ↔ ¬ ∀y ∈ ℕ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
7472, 73bitr 151 . . . . . 6 (∃y ∈ ℕ ∃w ∈ ℕ ∀z ∈ ℕ ¬ (yzwz) ↔ ¬ ∀y ∈ ℕ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
7566, 67, 743imtr3 191 . . . . 5 ((∃y ∈ ℕ ∀z ∈ ℕ (yz → (norm ‘((Fz) −v A)) < ((norm ‘(Av B)) / 2)) ∧ ∃w ∈ ℕ ∀z ∈ ℕ (wz → (norm ‘((Fz) −v B)) < ((norm ‘(Av B)) / 2))) → ¬ ∀y ∈ ℕ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
7617, 39, 753syl 21 . . . 4 (0 < (norm ‘(Av B)) → ¬ ∀y ∈ ℕ ∀w ∈ ℕ ∃z ∈ ℕ (yzwz))
772, 76mt2 96 . . 3 ¬ 0 < (norm ‘(Av B))
78 normgt0t 5078 . . . . 5 ((Av B) ∈ ℋ → (¬ (Av B) = 0v ↔ 0 < (norm ‘(Av B))))
7913, 78ax-mp 6 . . . 4 (¬ (Av B) = 0v ↔ 0 < (norm ‘(Av B)))
8079bicon1i 193 . . 3 (¬ 0 < (norm ‘(Av B)) ↔ (Av B) = 0v)
8177, 80mpbi 164 . 2 (Av B) = 0v
828, 12hvsubeq0 5035 . 2 ((Av B) = 0vA = B)
8381, 82mpbi 164 1 A = B
Colors of variables: wff set class
Syntax hints:  ¬ wn 1   → wi 2   ↔ wb 127   ∧ wa 196   = wceq 1091   ∈ wcel 1092  ∀wral 1201  ∃wrex 1202  Vcvv 1348   class class class wbr 2054  –→wf 2418   ‘cfv 2422  (class class class)co 3001  ℝcr 4027  0cc0 4028   < clt 4033   / cdiv 4091   ≤ cle 4092  ℕcn 4093  2c2 4454   ℋ chil 4958  0vc0v 4961   −v cmv 4962  normcno 4964   ⇝v chli 4966
This theorem is referenced by:  hlimuni 5144
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-un 1076  ax-pow 1077  ax-reg 1078  ax-inf 1079  ax-hvaddcl 4984  ax-hvcom 4985  ax-hvass 4986  ax-hvzercl 4987  ax-hvaddid 4988  ax-hvmulcl 4989  ax-hvmulid 4991  ax-hvmulass 4992  ax-hvdistr1 4993  ax-hvdistr2 4994  ax-hvmulzer 4995  ax-hicl 5043  ax-his1 5045  ax-his2 5046  ax-his3 5047  ax-his4 5048
This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3or 582  df-3an 583  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-ne 1192  df-ral 1205  df-rex 1206  df-reu 1207  df-rab 1208  df-v 1349  df-sbc 1441  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-pss 1494  df-nul 1708  df-if 1777  df-pw 1799  df-sn 1811  df-pr 1812  df-tp 1814  df-op 1815  df-uni 1920  df-int 1966  df-iun 1996  df-tr 2042  df-br 2063  df-opab 2098  df-eprel 2122  df-id 2125  df-po 2128  df-so 2138  df-sup 2154  df-fr 2169  df-we 2186  df-ord 2202  df-on 2203  df-lim 2204  df-suc 2205  df-om 2373  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-res 2430  df-ima 2431  df-fun 2432  df-fn 2433  df-f 2434  df-f1 2435  df-fo 2436  df-f1o 2437  df-fv 2438  df-rdg 2970  df-opr 3003  df-oprab 3004  df-1st 3087  df-2nd 3088  df-1o 3104  df-oadd 3106  df-omul 3107  df-er 3200  df-ec 3202  df-qs 3205  df-ni 3794  df-pli 3795  df-mi 3796  df-lti 3797  df-plpq 3829  df-mpq 3830  df-enq 3831  df-nq 3832  df-plq 3833  df-mq 3834  df-rq 3835  df-ltq 3836  df-1q 3837  df-np 3880  df-1p 3881  df-plp 3882  df-mp 3883  df-ltp 3884  df-plpr 3958  df-mpr 3959  df-enr 3960  df-nr 3961  df-plr 3962  df-mr 3963  df-ltr 3964  df-0r 3965  df-1r 3966  df-m1r 3967  df-c 4034  df-0 4035  df-1 4036  df-i 4037  df-r 4038  df-plus 4039  df-mul 4040  df-lt 4041  df-sub 4133  df-neg 4135  df-div 4216  df-le 4277  df-n 4423  df-2 4462  df-3 4463  df-4 4464  df-n0 4535  df-z 4564  df-seq 4661  df-exp 4676  df-sqr 4728  df-re 4790  df-im 4791  df-cj 4792  df-abs 4793  df-hvsub 4996  df-hnorm 5074  df-hlim 5107
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