Metamath Proof Explorer


Theorem crctcshlem2

Description: Lemma for crctcsh . (Contributed by AV, 10-Mar-2021)

Ref Expression
Hypotheses crctcsh.v
|- V = ( Vtx ` G )
crctcsh.i
|- I = ( iEdg ` G )
crctcsh.d
|- ( ph -> F ( Circuits ` G ) P )
crctcsh.n
|- N = ( # ` F )
crctcsh.s
|- ( ph -> S e. ( 0 ..^ N ) )
crctcsh.h
|- H = ( F cyclShift S )
Assertion crctcshlem2
|- ( ph -> ( # ` H ) = N )

Proof

Step Hyp Ref Expression
1 crctcsh.v
 |-  V = ( Vtx ` G )
2 crctcsh.i
 |-  I = ( iEdg ` G )
3 crctcsh.d
 |-  ( ph -> F ( Circuits ` G ) P )
4 crctcsh.n
 |-  N = ( # ` F )
5 crctcsh.s
 |-  ( ph -> S e. ( 0 ..^ N ) )
6 crctcsh.h
 |-  H = ( F cyclShift S )
7 crctiswlk
 |-  ( F ( Circuits ` G ) P -> F ( Walks ` G ) P )
8 2 wlkf
 |-  ( F ( Walks ` G ) P -> F e. Word dom I )
9 3 7 8 3syl
 |-  ( ph -> F e. Word dom I )
10 elfzoelz
 |-  ( S e. ( 0 ..^ N ) -> S e. ZZ )
11 5 10 syl
 |-  ( ph -> S e. ZZ )
12 cshwlen
 |-  ( ( F e. Word dom I /\ S e. ZZ ) -> ( # ` ( F cyclShift S ) ) = ( # ` F ) )
13 9 11 12 syl2anc
 |-  ( ph -> ( # ` ( F cyclShift S ) ) = ( # ` F ) )
14 6 fveq2i
 |-  ( # ` H ) = ( # ` ( F cyclShift S ) )
15 13 14 4 3eqtr4g
 |-  ( ph -> ( # ` H ) = N )