Metamath Proof Explorer


Theorem upgrimtrls

Description: Graph isomorphisms between simple pseudographs map trails onto trails. (Contributed by AV, 29-Oct-2025)

Ref Expression
Hypotheses upgrimwlk.i
|- I = ( iEdg ` G )
upgrimwlk.j
|- J = ( iEdg ` H )
upgrimwlk.g
|- ( ph -> G e. USPGraph )
upgrimwlk.h
|- ( ph -> H e. USPGraph )
upgrimwlk.n
|- ( ph -> N e. ( G GraphIso H ) )
upgrimwlk.e
|- E = ( x e. dom F |-> ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) )
upgrimtrls.t
|- ( ph -> F ( Trails ` G ) P )
Assertion upgrimtrls
|- ( ph -> E ( Trails ` H ) ( N o. P ) )

Proof

Step Hyp Ref Expression
1 upgrimwlk.i
 |-  I = ( iEdg ` G )
2 upgrimwlk.j
 |-  J = ( iEdg ` H )
3 upgrimwlk.g
 |-  ( ph -> G e. USPGraph )
4 upgrimwlk.h
 |-  ( ph -> H e. USPGraph )
5 upgrimwlk.n
 |-  ( ph -> N e. ( G GraphIso H ) )
6 upgrimwlk.e
 |-  E = ( x e. dom F |-> ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) )
7 upgrimtrls.t
 |-  ( ph -> F ( Trails ` G ) P )
8 trliswlk
 |-  ( F ( Trails ` G ) P -> F ( Walks ` G ) P )
9 7 8 syl
 |-  ( ph -> F ( Walks ` G ) P )
10 1 2 3 4 5 6 9 upgrimwlk
 |-  ( ph -> E ( Walks ` H ) ( N o. P ) )
11 4 adantr
 |-  ( ( ph /\ x e. dom F ) -> H e. USPGraph )
12 2 uspgrf1oedg
 |-  ( H e. USPGraph -> J : dom J -1-1-onto-> ( Edg ` H ) )
13 11 12 syl
 |-  ( ( ph /\ x e. dom F ) -> J : dom J -1-1-onto-> ( Edg ` H ) )
14 1 2 3 4 5 6 7 upgrimtrlslem1
 |-  ( ( ph /\ x e. dom F ) -> ( N " ( I ` ( F ` x ) ) ) e. ( Edg ` H ) )
15 f1ocnvdm
 |-  ( ( J : dom J -1-1-onto-> ( Edg ` H ) /\ ( N " ( I ` ( F ` x ) ) ) e. ( Edg ` H ) ) -> ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) e. dom J )
16 13 14 15 syl2anc
 |-  ( ( ph /\ x e. dom F ) -> ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) e. dom J )
17 16 ralrimiva
 |-  ( ph -> A. x e. dom F ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) e. dom J )
18 1 2 3 4 5 6 7 upgrimtrlslem2
 |-  ( ( ph /\ ( x e. dom F /\ y e. dom F ) ) -> ( ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) = ( `' J ` ( N " ( I ` ( F ` y ) ) ) ) -> x = y ) )
19 18 ralrimivva
 |-  ( ph -> A. x e. dom F A. y e. dom F ( ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) = ( `' J ` ( N " ( I ` ( F ` y ) ) ) ) -> x = y ) )
20 2fveq3
 |-  ( x = y -> ( I ` ( F ` x ) ) = ( I ` ( F ` y ) ) )
21 20 imaeq2d
 |-  ( x = y -> ( N " ( I ` ( F ` x ) ) ) = ( N " ( I ` ( F ` y ) ) ) )
22 21 fveq2d
 |-  ( x = y -> ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) = ( `' J ` ( N " ( I ` ( F ` y ) ) ) ) )
23 6 22 f1mpt
 |-  ( E : dom F -1-1-> dom J <-> ( A. x e. dom F ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) e. dom J /\ A. x e. dom F A. y e. dom F ( ( `' J ` ( N " ( I ` ( F ` x ) ) ) ) = ( `' J ` ( N " ( I ` ( F ` y ) ) ) ) -> x = y ) ) )
24 17 19 23 sylanbrc
 |-  ( ph -> E : dom F -1-1-> dom J )
25 eqidd
 |-  ( ph -> E = E )
26 1 wlkf
 |-  ( F ( Walks ` G ) P -> F e. Word dom I )
27 7 8 26 3syl
 |-  ( ph -> F e. Word dom I )
28 1 2 3 4 5 6 27 upgrimwlklem1
 |-  ( ph -> ( # ` E ) = ( # ` F ) )
29 28 oveq2d
 |-  ( ph -> ( 0 ..^ ( # ` E ) ) = ( 0 ..^ ( # ` F ) ) )
30 wrddm
 |-  ( F e. Word dom I -> dom F = ( 0 ..^ ( # ` F ) ) )
31 8 26 30 3syl
 |-  ( F ( Trails ` G ) P -> dom F = ( 0 ..^ ( # ` F ) ) )
32 7 31 syl
 |-  ( ph -> dom F = ( 0 ..^ ( # ` F ) ) )
33 29 32 eqtr4d
 |-  ( ph -> ( 0 ..^ ( # ` E ) ) = dom F )
34 eqidd
 |-  ( ph -> dom J = dom J )
35 25 33 34 f1eq123d
 |-  ( ph -> ( E : ( 0 ..^ ( # ` E ) ) -1-1-> dom J <-> E : dom F -1-1-> dom J ) )
36 24 35 mpbird
 |-  ( ph -> E : ( 0 ..^ ( # ` E ) ) -1-1-> dom J )
37 df-f1
 |-  ( E : ( 0 ..^ ( # ` E ) ) -1-1-> dom J <-> ( E : ( 0 ..^ ( # ` E ) ) --> dom J /\ Fun `' E ) )
38 37 simprbi
 |-  ( E : ( 0 ..^ ( # ` E ) ) -1-1-> dom J -> Fun `' E )
39 36 38 syl
 |-  ( ph -> Fun `' E )
40 istrl
 |-  ( E ( Trails ` H ) ( N o. P ) <-> ( E ( Walks ` H ) ( N o. P ) /\ Fun `' E ) )
41 10 39 40 sylanbrc
 |-  ( ph -> E ( Trails ` H ) ( N o. P ) )