Metamath Proof Explorer


Theorem efgrelexlemb

Description: If two words A , B are related under the free group equivalence, then there exist two extension sequences a , b such that a ends at A , b ends at B , and a and B have the same starting point. (Contributed by Mario Carneiro, 1-Oct-2015)

Ref Expression
Hypotheses efgval.w
|- W = ( _I ` Word ( I X. 2o ) )
efgval.r
|- .~ = ( ~FG ` I )
efgval2.m
|- M = ( y e. I , z e. 2o |-> <. y , ( 1o \ z ) >. )
efgval2.t
|- T = ( v e. W |-> ( n e. ( 0 ... ( # ` v ) ) , w e. ( I X. 2o ) |-> ( v splice <. n , n , <" w ( M ` w ) "> >. ) ) )
efgred.d
|- D = ( W \ U_ x e. W ran ( T ` x ) )
efgred.s
|- S = ( m e. { t e. ( Word W \ { (/) } ) | ( ( t ` 0 ) e. D /\ A. k e. ( 1 ..^ ( # ` t ) ) ( t ` k ) e. ran ( T ` ( t ` ( k - 1 ) ) ) ) } |-> ( m ` ( ( # ` m ) - 1 ) ) )
efgrelexlem.1
|- L = { <. i , j >. | E. c e. ( `' S " { i } ) E. d e. ( `' S " { j } ) ( c ` 0 ) = ( d ` 0 ) }
Assertion efgrelexlemb
|- .~ C_ L

Proof

Step Hyp Ref Expression
1 efgval.w
 |-  W = ( _I ` Word ( I X. 2o ) )
2 efgval.r
 |-  .~ = ( ~FG ` I )
3 efgval2.m
 |-  M = ( y e. I , z e. 2o |-> <. y , ( 1o \ z ) >. )
4 efgval2.t
 |-  T = ( v e. W |-> ( n e. ( 0 ... ( # ` v ) ) , w e. ( I X. 2o ) |-> ( v splice <. n , n , <" w ( M ` w ) "> >. ) ) )
5 efgred.d
 |-  D = ( W \ U_ x e. W ran ( T ` x ) )
6 efgred.s
 |-  S = ( m e. { t e. ( Word W \ { (/) } ) | ( ( t ` 0 ) e. D /\ A. k e. ( 1 ..^ ( # ` t ) ) ( t ` k ) e. ran ( T ` ( t ` ( k - 1 ) ) ) ) } |-> ( m ` ( ( # ` m ) - 1 ) ) )
7 efgrelexlem.1
 |-  L = { <. i , j >. | E. c e. ( `' S " { i } ) E. d e. ( `' S " { j } ) ( c ` 0 ) = ( d ` 0 ) }
8 1 2 3 4 efgval2
 |-  .~ = |^| { r | ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) }
9 7 relopabiv
 |-  Rel L
10 9 a1i
 |-  ( T. -> Rel L )
11 simpr
 |-  ( ( T. /\ f L g ) -> f L g )
12 eqcom
 |-  ( ( a ` 0 ) = ( b ` 0 ) <-> ( b ` 0 ) = ( a ` 0 ) )
13 12 2rexbii
 |-  ( E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) <-> E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( b ` 0 ) = ( a ` 0 ) )
14 rexcom
 |-  ( E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( b ` 0 ) = ( a ` 0 ) <-> E. b e. ( `' S " { g } ) E. a e. ( `' S " { f } ) ( b ` 0 ) = ( a ` 0 ) )
15 13 14 bitri
 |-  ( E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) <-> E. b e. ( `' S " { g } ) E. a e. ( `' S " { f } ) ( b ` 0 ) = ( a ` 0 ) )
16 1 2 3 4 5 6 7 efgrelexlema
 |-  ( f L g <-> E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) )
17 1 2 3 4 5 6 7 efgrelexlema
 |-  ( g L f <-> E. b e. ( `' S " { g } ) E. a e. ( `' S " { f } ) ( b ` 0 ) = ( a ` 0 ) )
18 15 16 17 3bitr4i
 |-  ( f L g <-> g L f )
19 11 18 sylib
 |-  ( ( T. /\ f L g ) -> g L f )
20 1 2 3 4 5 6 7 efgrelexlema
 |-  ( g L h <-> E. r e. ( `' S " { g } ) E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) )
21 reeanv
 |-  ( E. a e. ( `' S " { f } ) E. r e. ( `' S " { g } ) ( E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) /\ E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) ) <-> ( E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) /\ E. r e. ( `' S " { g } ) E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) ) )
22 1 2 3 4 5 6 efgsfo
 |-  S : dom S -onto-> W
23 fofn
 |-  ( S : dom S -onto-> W -> S Fn dom S )
24 22 23 ax-mp
 |-  S Fn dom S
25 fniniseg
 |-  ( S Fn dom S -> ( r e. ( `' S " { g } ) <-> ( r e. dom S /\ ( S ` r ) = g ) ) )
26 24 25 ax-mp
 |-  ( r e. ( `' S " { g } ) <-> ( r e. dom S /\ ( S ` r ) = g ) )
27 fniniseg
 |-  ( S Fn dom S -> ( b e. ( `' S " { g } ) <-> ( b e. dom S /\ ( S ` b ) = g ) ) )
28 24 27 ax-mp
 |-  ( b e. ( `' S " { g } ) <-> ( b e. dom S /\ ( S ` b ) = g ) )
29 eqtr3
 |-  ( ( ( S ` r ) = g /\ ( S ` b ) = g ) -> ( S ` r ) = ( S ` b ) )
30 1 2 3 4 5 6 efgred
 |-  ( ( r e. dom S /\ b e. dom S /\ ( S ` r ) = ( S ` b ) ) -> ( r ` 0 ) = ( b ` 0 ) )
31 30 eqcomd
 |-  ( ( r e. dom S /\ b e. dom S /\ ( S ` r ) = ( S ` b ) ) -> ( b ` 0 ) = ( r ` 0 ) )
32 31 3expa
 |-  ( ( ( r e. dom S /\ b e. dom S ) /\ ( S ` r ) = ( S ` b ) ) -> ( b ` 0 ) = ( r ` 0 ) )
33 29 32 sylan2
 |-  ( ( ( r e. dom S /\ b e. dom S ) /\ ( ( S ` r ) = g /\ ( S ` b ) = g ) ) -> ( b ` 0 ) = ( r ` 0 ) )
34 33 an4s
 |-  ( ( ( r e. dom S /\ ( S ` r ) = g ) /\ ( b e. dom S /\ ( S ` b ) = g ) ) -> ( b ` 0 ) = ( r ` 0 ) )
35 26 28 34 syl2anb
 |-  ( ( r e. ( `' S " { g } ) /\ b e. ( `' S " { g } ) ) -> ( b ` 0 ) = ( r ` 0 ) )
36 eqeq2
 |-  ( ( r ` 0 ) = ( s ` 0 ) -> ( ( b ` 0 ) = ( r ` 0 ) <-> ( b ` 0 ) = ( s ` 0 ) ) )
37 35 36 syl5ibcom
 |-  ( ( r e. ( `' S " { g } ) /\ b e. ( `' S " { g } ) ) -> ( ( r ` 0 ) = ( s ` 0 ) -> ( b ` 0 ) = ( s ` 0 ) ) )
38 37 reximdv
 |-  ( ( r e. ( `' S " { g } ) /\ b e. ( `' S " { g } ) ) -> ( E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) -> E. s e. ( `' S " { h } ) ( b ` 0 ) = ( s ` 0 ) ) )
39 eqeq1
 |-  ( ( a ` 0 ) = ( b ` 0 ) -> ( ( a ` 0 ) = ( s ` 0 ) <-> ( b ` 0 ) = ( s ` 0 ) ) )
40 39 rexbidv
 |-  ( ( a ` 0 ) = ( b ` 0 ) -> ( E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) <-> E. s e. ( `' S " { h } ) ( b ` 0 ) = ( s ` 0 ) ) )
41 40 imbi2d
 |-  ( ( a ` 0 ) = ( b ` 0 ) -> ( ( E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) -> E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) ) <-> ( E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) -> E. s e. ( `' S " { h } ) ( b ` 0 ) = ( s ` 0 ) ) ) )
42 38 41 syl5ibrcom
 |-  ( ( r e. ( `' S " { g } ) /\ b e. ( `' S " { g } ) ) -> ( ( a ` 0 ) = ( b ` 0 ) -> ( E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) -> E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) ) ) )
43 42 rexlimdva
 |-  ( r e. ( `' S " { g } ) -> ( E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) -> ( E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) -> E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) ) ) )
44 43 impd
 |-  ( r e. ( `' S " { g } ) -> ( ( E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) /\ E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) ) -> E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) ) )
45 44 rexlimiv
 |-  ( E. r e. ( `' S " { g } ) ( E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) /\ E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) ) -> E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) )
46 45 reximi
 |-  ( E. a e. ( `' S " { f } ) E. r e. ( `' S " { g } ) ( E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) /\ E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) ) -> E. a e. ( `' S " { f } ) E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) )
47 21 46 sylbir
 |-  ( ( E. a e. ( `' S " { f } ) E. b e. ( `' S " { g } ) ( a ` 0 ) = ( b ` 0 ) /\ E. r e. ( `' S " { g } ) E. s e. ( `' S " { h } ) ( r ` 0 ) = ( s ` 0 ) ) -> E. a e. ( `' S " { f } ) E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) )
48 16 20 47 syl2anb
 |-  ( ( f L g /\ g L h ) -> E. a e. ( `' S " { f } ) E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) )
49 1 2 3 4 5 6 7 efgrelexlema
 |-  ( f L h <-> E. a e. ( `' S " { f } ) E. s e. ( `' S " { h } ) ( a ` 0 ) = ( s ` 0 ) )
50 48 49 sylibr
 |-  ( ( f L g /\ g L h ) -> f L h )
51 50 adantl
 |-  ( ( T. /\ ( f L g /\ g L h ) ) -> f L h )
52 eqid
 |-  ( a ` 0 ) = ( a ` 0 )
53 fveq1
 |-  ( b = a -> ( b ` 0 ) = ( a ` 0 ) )
54 53 rspceeqv
 |-  ( ( a e. ( `' S " { f } ) /\ ( a ` 0 ) = ( a ` 0 ) ) -> E. b e. ( `' S " { f } ) ( a ` 0 ) = ( b ` 0 ) )
55 52 54 mpan2
 |-  ( a e. ( `' S " { f } ) -> E. b e. ( `' S " { f } ) ( a ` 0 ) = ( b ` 0 ) )
56 55 pm4.71i
 |-  ( a e. ( `' S " { f } ) <-> ( a e. ( `' S " { f } ) /\ E. b e. ( `' S " { f } ) ( a ` 0 ) = ( b ` 0 ) ) )
57 fniniseg
 |-  ( S Fn dom S -> ( a e. ( `' S " { f } ) <-> ( a e. dom S /\ ( S ` a ) = f ) ) )
58 24 57 ax-mp
 |-  ( a e. ( `' S " { f } ) <-> ( a e. dom S /\ ( S ` a ) = f ) )
59 56 58 bitr3i
 |-  ( ( a e. ( `' S " { f } ) /\ E. b e. ( `' S " { f } ) ( a ` 0 ) = ( b ` 0 ) ) <-> ( a e. dom S /\ ( S ` a ) = f ) )
60 59 rexbii2
 |-  ( E. a e. ( `' S " { f } ) E. b e. ( `' S " { f } ) ( a ` 0 ) = ( b ` 0 ) <-> E. a e. dom S ( S ` a ) = f )
61 1 2 3 4 5 6 7 efgrelexlema
 |-  ( f L f <-> E. a e. ( `' S " { f } ) E. b e. ( `' S " { f } ) ( a ` 0 ) = ( b ` 0 ) )
62 forn
 |-  ( S : dom S -onto-> W -> ran S = W )
63 22 62 ax-mp
 |-  ran S = W
64 63 eleq2i
 |-  ( f e. ran S <-> f e. W )
65 fvelrnb
 |-  ( S Fn dom S -> ( f e. ran S <-> E. a e. dom S ( S ` a ) = f ) )
66 24 65 ax-mp
 |-  ( f e. ran S <-> E. a e. dom S ( S ` a ) = f )
67 64 66 bitr3i
 |-  ( f e. W <-> E. a e. dom S ( S ` a ) = f )
68 60 61 67 3bitr4ri
 |-  ( f e. W <-> f L f )
69 68 a1i
 |-  ( T. -> ( f e. W <-> f L f ) )
70 10 19 51 69 iserd
 |-  ( T. -> L Er W )
71 70 mptru
 |-  L Er W
72 simpl
 |-  ( ( a e. W /\ b e. ran ( T ` a ) ) -> a e. W )
73 foelrn
 |-  ( ( S : dom S -onto-> W /\ a e. W ) -> E. r e. dom S a = ( S ` r ) )
74 22 72 73 sylancr
 |-  ( ( a e. W /\ b e. ran ( T ` a ) ) -> E. r e. dom S a = ( S ` r ) )
75 simprl
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> r e. dom S )
76 simprr
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> a = ( S ` r ) )
77 76 eqcomd
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( S ` r ) = a )
78 fniniseg
 |-  ( S Fn dom S -> ( r e. ( `' S " { a } ) <-> ( r e. dom S /\ ( S ` r ) = a ) ) )
79 24 78 ax-mp
 |-  ( r e. ( `' S " { a } ) <-> ( r e. dom S /\ ( S ` r ) = a ) )
80 75 77 79 sylanbrc
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> r e. ( `' S " { a } ) )
81 simplr
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> b e. ran ( T ` a ) )
82 76 fveq2d
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( T ` a ) = ( T ` ( S ` r ) ) )
83 82 rneqd
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ran ( T ` a ) = ran ( T ` ( S ` r ) ) )
84 81 83 eleqtrd
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> b e. ran ( T ` ( S ` r ) ) )
85 1 2 3 4 5 6 efgsp1
 |-  ( ( r e. dom S /\ b e. ran ( T ` ( S ` r ) ) ) -> ( r ++ <" b "> ) e. dom S )
86 75 84 85 syl2anc
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( r ++ <" b "> ) e. dom S )
87 1 2 3 4 5 6 efgsdm
 |-  ( r e. dom S <-> ( r e. ( Word W \ { (/) } ) /\ ( r ` 0 ) e. D /\ A. i e. ( 1 ..^ ( # ` r ) ) ( r ` i ) e. ran ( T ` ( r ` ( i - 1 ) ) ) ) )
88 87 simp1bi
 |-  ( r e. dom S -> r e. ( Word W \ { (/) } ) )
89 88 ad2antrl
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> r e. ( Word W \ { (/) } ) )
90 89 eldifad
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> r e. Word W )
91 1 2 3 4 efgtf
 |-  ( a e. W -> ( ( T ` a ) = ( f e. ( 0 ... ( # ` a ) ) , g e. ( I X. 2o ) |-> ( a splice <. f , f , <" g ( M ` g ) "> >. ) ) /\ ( T ` a ) : ( ( 0 ... ( # ` a ) ) X. ( I X. 2o ) ) --> W ) )
92 91 simprd
 |-  ( a e. W -> ( T ` a ) : ( ( 0 ... ( # ` a ) ) X. ( I X. 2o ) ) --> W )
93 92 frnd
 |-  ( a e. W -> ran ( T ` a ) C_ W )
94 93 sselda
 |-  ( ( a e. W /\ b e. ran ( T ` a ) ) -> b e. W )
95 94 adantr
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> b e. W )
96 1 2 3 4 5 6 efgsval2
 |-  ( ( r e. Word W /\ b e. W /\ ( r ++ <" b "> ) e. dom S ) -> ( S ` ( r ++ <" b "> ) ) = b )
97 90 95 86 96 syl3anc
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( S ` ( r ++ <" b "> ) ) = b )
98 fniniseg
 |-  ( S Fn dom S -> ( ( r ++ <" b "> ) e. ( `' S " { b } ) <-> ( ( r ++ <" b "> ) e. dom S /\ ( S ` ( r ++ <" b "> ) ) = b ) ) )
99 24 98 ax-mp
 |-  ( ( r ++ <" b "> ) e. ( `' S " { b } ) <-> ( ( r ++ <" b "> ) e. dom S /\ ( S ` ( r ++ <" b "> ) ) = b ) )
100 86 97 99 sylanbrc
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( r ++ <" b "> ) e. ( `' S " { b } ) )
101 95 s1cld
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> <" b "> e. Word W )
102 eldifsn
 |-  ( r e. ( Word W \ { (/) } ) <-> ( r e. Word W /\ r =/= (/) ) )
103 lennncl
 |-  ( ( r e. Word W /\ r =/= (/) ) -> ( # ` r ) e. NN )
104 102 103 sylbi
 |-  ( r e. ( Word W \ { (/) } ) -> ( # ` r ) e. NN )
105 89 104 syl
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( # ` r ) e. NN )
106 lbfzo0
 |-  ( 0 e. ( 0 ..^ ( # ` r ) ) <-> ( # ` r ) e. NN )
107 105 106 sylibr
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> 0 e. ( 0 ..^ ( # ` r ) ) )
108 ccatval1
 |-  ( ( r e. Word W /\ <" b "> e. Word W /\ 0 e. ( 0 ..^ ( # ` r ) ) ) -> ( ( r ++ <" b "> ) ` 0 ) = ( r ` 0 ) )
109 90 101 107 108 syl3anc
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( ( r ++ <" b "> ) ` 0 ) = ( r ` 0 ) )
110 109 eqcomd
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> ( r ` 0 ) = ( ( r ++ <" b "> ) ` 0 ) )
111 fveq1
 |-  ( s = ( r ++ <" b "> ) -> ( s ` 0 ) = ( ( r ++ <" b "> ) ` 0 ) )
112 111 rspceeqv
 |-  ( ( ( r ++ <" b "> ) e. ( `' S " { b } ) /\ ( r ` 0 ) = ( ( r ++ <" b "> ) ` 0 ) ) -> E. s e. ( `' S " { b } ) ( r ` 0 ) = ( s ` 0 ) )
113 100 110 112 syl2anc
 |-  ( ( ( a e. W /\ b e. ran ( T ` a ) ) /\ ( r e. dom S /\ a = ( S ` r ) ) ) -> E. s e. ( `' S " { b } ) ( r ` 0 ) = ( s ` 0 ) )
114 74 80 113 reximssdv
 |-  ( ( a e. W /\ b e. ran ( T ` a ) ) -> E. r e. ( `' S " { a } ) E. s e. ( `' S " { b } ) ( r ` 0 ) = ( s ` 0 ) )
115 1 2 3 4 5 6 7 efgrelexlema
 |-  ( a L b <-> E. r e. ( `' S " { a } ) E. s e. ( `' S " { b } ) ( r ` 0 ) = ( s ` 0 ) )
116 114 115 sylibr
 |-  ( ( a e. W /\ b e. ran ( T ` a ) ) -> a L b )
117 vex
 |-  b e. _V
118 vex
 |-  a e. _V
119 117 118 elec
 |-  ( b e. [ a ] L <-> a L b )
120 116 119 sylibr
 |-  ( ( a e. W /\ b e. ran ( T ` a ) ) -> b e. [ a ] L )
121 120 ex
 |-  ( a e. W -> ( b e. ran ( T ` a ) -> b e. [ a ] L ) )
122 121 ssrdv
 |-  ( a e. W -> ran ( T ` a ) C_ [ a ] L )
123 122 rgen
 |-  A. a e. W ran ( T ` a ) C_ [ a ] L
124 1 fvexi
 |-  W e. _V
125 erex
 |-  ( L Er W -> ( W e. _V -> L e. _V ) )
126 71 124 125 mp2
 |-  L e. _V
127 ereq1
 |-  ( r = L -> ( r Er W <-> L Er W ) )
128 eceq2
 |-  ( r = L -> [ a ] r = [ a ] L )
129 128 sseq2d
 |-  ( r = L -> ( ran ( T ` a ) C_ [ a ] r <-> ran ( T ` a ) C_ [ a ] L ) )
130 129 ralbidv
 |-  ( r = L -> ( A. a e. W ran ( T ` a ) C_ [ a ] r <-> A. a e. W ran ( T ` a ) C_ [ a ] L ) )
131 127 130 anbi12d
 |-  ( r = L -> ( ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) <-> ( L Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] L ) ) )
132 126 131 elab
 |-  ( L e. { r | ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) } <-> ( L Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] L ) )
133 71 123 132 mpbir2an
 |-  L e. { r | ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) }
134 intss1
 |-  ( L e. { r | ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) } -> |^| { r | ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) } C_ L )
135 133 134 ax-mp
 |-  |^| { r | ( r Er W /\ A. a e. W ran ( T ` a ) C_ [ a ] r ) } C_ L
136 8 135 eqsstri
 |-  .~ C_ L