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Theorem wlkiswwlks1 28759
Description: The sequence of vertices in a walk is a walk as word in a pseudograph. (Contributed by Alexander van der Vekens, 20-Jul-2018.) (Revised by AV, 9-Apr-2021.)
Assertion
Ref Expression
wlkiswwlks1 (𝐺 ∈ UPGraph → (𝐹(Walks‘𝐺)𝑃𝑃 ∈ (WWalks‘𝐺)))

Proof of Theorem wlkiswwlks1
Dummy variable 𝑖 is distinct from all other variables.
StepHypRef Expression
1 wlkn0 28516 . 2 (𝐹(Walks‘𝐺)𝑃𝑃 ≠ ∅)
2 eqid 2736 . . . 4 (Vtx‘𝐺) = (Vtx‘𝐺)
3 eqid 2736 . . . 4 (iEdg‘𝐺) = (iEdg‘𝐺)
42, 3upgriswlk 28536 . . 3 (𝐺 ∈ UPGraph → (𝐹(Walks‘𝐺)𝑃 ↔ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})))
5 simpr 485 . . . . . 6 (((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) ∧ 𝑃 ≠ ∅) → 𝑃 ≠ ∅)
6 ffz0iswrd 14428 . . . . . . . 8 (𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) → 𝑃 ∈ Word (Vtx‘𝐺))
763ad2ant2 1134 . . . . . . 7 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))}) → 𝑃 ∈ Word (Vtx‘𝐺))
87ad2antlr 725 . . . . . 6 (((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) ∧ 𝑃 ≠ ∅) → 𝑃 ∈ Word (Vtx‘𝐺))
9 upgruhgr 28000 . . . . . . . . . . . . . . . . . 18 (𝐺 ∈ UPGraph → 𝐺 ∈ UHGraph)
103uhgrfun 27964 . . . . . . . . . . . . . . . . . 18 (𝐺 ∈ UHGraph → Fun (iEdg‘𝐺))
11 funfn 6531 . . . . . . . . . . . . . . . . . . 19 (Fun (iEdg‘𝐺) ↔ (iEdg‘𝐺) Fn dom (iEdg‘𝐺))
1211biimpi 215 . . . . . . . . . . . . . . . . . 18 (Fun (iEdg‘𝐺) → (iEdg‘𝐺) Fn dom (iEdg‘𝐺))
139, 10, 123syl 18 . . . . . . . . . . . . . . . . 17 (𝐺 ∈ UPGraph → (iEdg‘𝐺) Fn dom (iEdg‘𝐺))
1413ad2antlr 725 . . . . . . . . . . . . . . . 16 ((((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) ∧ 𝐺 ∈ UPGraph) ∧ 𝑖 ∈ (0..^(♯‘𝐹))) → (iEdg‘𝐺) Fn dom (iEdg‘𝐺))
15 wrdsymbcl 14414 . . . . . . . . . . . . . . . . 17 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑖 ∈ (0..^(♯‘𝐹))) → (𝐹𝑖) ∈ dom (iEdg‘𝐺))
1615ad4ant14 750 . . . . . . . . . . . . . . . 16 ((((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) ∧ 𝐺 ∈ UPGraph) ∧ 𝑖 ∈ (0..^(♯‘𝐹))) → (𝐹𝑖) ∈ dom (iEdg‘𝐺))
17 fnfvelrn 7031 . . . . . . . . . . . . . . . 16 (((iEdg‘𝐺) Fn dom (iEdg‘𝐺) ∧ (𝐹𝑖) ∈ dom (iEdg‘𝐺)) → ((iEdg‘𝐺)‘(𝐹𝑖)) ∈ ran (iEdg‘𝐺))
1814, 16, 17syl2anc 584 . . . . . . . . . . . . . . 15 ((((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) ∧ 𝐺 ∈ UPGraph) ∧ 𝑖 ∈ (0..^(♯‘𝐹))) → ((iEdg‘𝐺)‘(𝐹𝑖)) ∈ ran (iEdg‘𝐺))
19 edgval 27947 . . . . . . . . . . . . . . 15 (Edg‘𝐺) = ran (iEdg‘𝐺)
2018, 19eleqtrrdi 2849 . . . . . . . . . . . . . 14 ((((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) ∧ 𝐺 ∈ UPGraph) ∧ 𝑖 ∈ (0..^(♯‘𝐹))) → ((iEdg‘𝐺)‘(𝐹𝑖)) ∈ (Edg‘𝐺))
21 eleq1 2825 . . . . . . . . . . . . . . 15 ({(𝑃𝑖), (𝑃‘(𝑖 + 1))} = ((iEdg‘𝐺)‘(𝐹𝑖)) → ({(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺) ↔ ((iEdg‘𝐺)‘(𝐹𝑖)) ∈ (Edg‘𝐺)))
2221eqcoms 2744 . . . . . . . . . . . . . 14 (((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))} → ({(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺) ↔ ((iEdg‘𝐺)‘(𝐹𝑖)) ∈ (Edg‘𝐺)))
2320, 22syl5ibrcom 246 . . . . . . . . . . . . 13 ((((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) ∧ 𝐺 ∈ UPGraph) ∧ 𝑖 ∈ (0..^(♯‘𝐹))) → (((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))} → {(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
2423ralimdva 3164 . . . . . . . . . . . 12 (((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) ∧ 𝐺 ∈ UPGraph) → (∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))} → ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
2524ex 413 . . . . . . . . . . 11 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) → (𝐺 ∈ UPGraph → (∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))} → ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺))))
2625com23 86 . . . . . . . . . 10 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) → (∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))} → (𝐺 ∈ UPGraph → ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺))))
27263impia 1117 . . . . . . . . 9 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))}) → (𝐺 ∈ UPGraph → ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
2827impcom 408 . . . . . . . 8 ((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) → ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺))
29 lencl 14420 . . . . . . . . . . . . . 14 (𝐹 ∈ Word dom (iEdg‘𝐺) → (♯‘𝐹) ∈ ℕ0)
30 ffz0hash 14343 . . . . . . . . . . . . . . . 16 (((♯‘𝐹) ∈ ℕ0𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) → (♯‘𝑃) = ((♯‘𝐹) + 1))
3130ex 413 . . . . . . . . . . . . . . 15 ((♯‘𝐹) ∈ ℕ0 → (𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) → (♯‘𝑃) = ((♯‘𝐹) + 1)))
32 oveq1 7363 . . . . . . . . . . . . . . . . 17 ((♯‘𝑃) = ((♯‘𝐹) + 1) → ((♯‘𝑃) − 1) = (((♯‘𝐹) + 1) − 1))
33 nn0cn 12422 . . . . . . . . . . . . . . . . . 18 ((♯‘𝐹) ∈ ℕ0 → (♯‘𝐹) ∈ ℂ)
34 pncan1 11578 . . . . . . . . . . . . . . . . . 18 ((♯‘𝐹) ∈ ℂ → (((♯‘𝐹) + 1) − 1) = (♯‘𝐹))
3533, 34syl 17 . . . . . . . . . . . . . . . . 17 ((♯‘𝐹) ∈ ℕ0 → (((♯‘𝐹) + 1) − 1) = (♯‘𝐹))
3632, 35sylan9eqr 2798 . . . . . . . . . . . . . . . 16 (((♯‘𝐹) ∈ ℕ0 ∧ (♯‘𝑃) = ((♯‘𝐹) + 1)) → ((♯‘𝑃) − 1) = (♯‘𝐹))
3736ex 413 . . . . . . . . . . . . . . 15 ((♯‘𝐹) ∈ ℕ0 → ((♯‘𝑃) = ((♯‘𝐹) + 1) → ((♯‘𝑃) − 1) = (♯‘𝐹)))
3831, 37syld 47 . . . . . . . . . . . . . 14 ((♯‘𝐹) ∈ ℕ0 → (𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) → ((♯‘𝑃) − 1) = (♯‘𝐹)))
3929, 38syl 17 . . . . . . . . . . . . 13 (𝐹 ∈ Word dom (iEdg‘𝐺) → (𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) → ((♯‘𝑃) − 1) = (♯‘𝐹)))
4039imp 407 . . . . . . . . . . . 12 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) → ((♯‘𝑃) − 1) = (♯‘𝐹))
4140oveq2d 7372 . . . . . . . . . . 11 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) → (0..^((♯‘𝑃) − 1)) = (0..^(♯‘𝐹)))
4241raleqdv 3313 . . . . . . . . . 10 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺)) → (∀𝑖 ∈ (0..^((♯‘𝑃) − 1)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺) ↔ ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
43423adant3 1132 . . . . . . . . 9 ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))}) → (∀𝑖 ∈ (0..^((♯‘𝑃) − 1)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺) ↔ ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
4443adantl 482 . . . . . . . 8 ((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) → (∀𝑖 ∈ (0..^((♯‘𝑃) − 1)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺) ↔ ∀𝑖 ∈ (0..^(♯‘𝐹)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
4528, 44mpbird 256 . . . . . . 7 ((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) → ∀𝑖 ∈ (0..^((♯‘𝑃) − 1)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺))
4645adantr 481 . . . . . 6 (((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) ∧ 𝑃 ≠ ∅) → ∀𝑖 ∈ (0..^((♯‘𝑃) − 1)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺))
47 eqid 2736 . . . . . . 7 (Edg‘𝐺) = (Edg‘𝐺)
482, 47iswwlks 28728 . . . . . 6 (𝑃 ∈ (WWalks‘𝐺) ↔ (𝑃 ≠ ∅ ∧ 𝑃 ∈ Word (Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^((♯‘𝑃) − 1)){(𝑃𝑖), (𝑃‘(𝑖 + 1))} ∈ (Edg‘𝐺)))
495, 8, 46, 48syl3anbrc 1343 . . . . 5 (((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) ∧ 𝑃 ≠ ∅) → 𝑃 ∈ (WWalks‘𝐺))
5049ex 413 . . . 4 ((𝐺 ∈ UPGraph ∧ (𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))})) → (𝑃 ≠ ∅ → 𝑃 ∈ (WWalks‘𝐺)))
5150ex 413 . . 3 (𝐺 ∈ UPGraph → ((𝐹 ∈ Word dom (iEdg‘𝐺) ∧ 𝑃:(0...(♯‘𝐹))⟶(Vtx‘𝐺) ∧ ∀𝑖 ∈ (0..^(♯‘𝐹))((iEdg‘𝐺)‘(𝐹𝑖)) = {(𝑃𝑖), (𝑃‘(𝑖 + 1))}) → (𝑃 ≠ ∅ → 𝑃 ∈ (WWalks‘𝐺))))
524, 51sylbid 239 . 2 (𝐺 ∈ UPGraph → (𝐹(Walks‘𝐺)𝑃 → (𝑃 ≠ ∅ → 𝑃 ∈ (WWalks‘𝐺))))
531, 52mpdi 45 1 (𝐺 ∈ UPGraph → (𝐹(Walks‘𝐺)𝑃𝑃 ∈ (WWalks‘𝐺)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 205  wa 396  w3a 1087   = wceq 1541  wcel 2106  wne 2943  wral 3064  c0 4282  {cpr 4588   class class class wbr 5105  dom cdm 5633  ran crn 5634  Fun wfun 6490   Fn wfn 6491  wf 6492  cfv 6496  (class class class)co 7356  cc 11048  0cc0 11050  1c1 11051   + caddc 11053  cmin 11384  0cn0 12412  ...cfz 13423  ..^cfzo 13566  chash 14229  Word cword 14401  Vtxcvtx 27894  iEdgciedg 27895  Edgcedg 27945  UHGraphcuhgr 27954  UPGraphcupgr 27978  Walkscwlks 28491  WWalkscwwlks 28717
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2707  ax-rep 5242  ax-sep 5256  ax-nul 5263  ax-pow 5320  ax-pr 5384  ax-un 7671  ax-cnex 11106  ax-resscn 11107  ax-1cn 11108  ax-icn 11109  ax-addcl 11110  ax-addrcl 11111  ax-mulcl 11112  ax-mulrcl 11113  ax-mulcom 11114  ax-addass 11115  ax-mulass 11116  ax-distr 11117  ax-i2m1 11118  ax-1ne0 11119  ax-1rid 11120  ax-rnegex 11121  ax-rrecex 11122  ax-cnre 11123  ax-pre-lttri 11124  ax-pre-lttrn 11125  ax-pre-ltadd 11126  ax-pre-mulgt0 11127
This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-ifp 1062  df-3or 1088  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-mo 2538  df-eu 2567  df-clab 2714  df-cleq 2728  df-clel 2814  df-nfc 2889  df-ne 2944  df-nel 3050  df-ral 3065  df-rex 3074  df-reu 3354  df-rab 3408  df-v 3447  df-sbc 3740  df-csb 3856  df-dif 3913  df-un 3915  df-in 3917  df-ss 3927  df-pss 3929  df-nul 4283  df-if 4487  df-pw 4562  df-sn 4587  df-pr 4589  df-op 4593  df-uni 4866  df-int 4908  df-iun 4956  df-br 5106  df-opab 5168  df-mpt 5189  df-tr 5223  df-id 5531  df-eprel 5537  df-po 5545  df-so 5546  df-fr 5588  df-we 5590  df-xp 5639  df-rel 5640  df-cnv 5641  df-co 5642  df-dm 5643  df-rn 5644  df-res 5645  df-ima 5646  df-pred 6253  df-ord 6320  df-on 6321  df-lim 6322  df-suc 6323  df-iota 6448  df-fun 6498  df-fn 6499  df-f 6500  df-f1 6501  df-fo 6502  df-f1o 6503  df-fv 6504  df-riota 7312  df-ov 7359  df-oprab 7360  df-mpo 7361  df-om 7802  df-1st 7920  df-2nd 7921  df-frecs 8211  df-wrecs 8242  df-recs 8316  df-rdg 8355  df-1o 8411  df-2o 8412  df-oadd 8415  df-er 8647  df-map 8766  df-pm 8767  df-en 8883  df-dom 8884  df-sdom 8885  df-fin 8886  df-dju 9836  df-card 9874  df-pnf 11190  df-mnf 11191  df-xr 11192  df-ltxr 11193  df-le 11194  df-sub 11386  df-neg 11387  df-nn 12153  df-2 12215  df-n0 12413  df-xnn0 12485  df-z 12499  df-uz 12763  df-fz 13424  df-fzo 13567  df-hash 14230  df-word 14402  df-edg 27946  df-uhgr 27956  df-upgr 27980  df-wlks 28494  df-wwlks 28722
This theorem is referenced by:  wlklnwwlkln1  28760  wlkiswwlks  28768  wlkiswwlkupgr  28770  elwspths2spth  28859
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