| Step | Hyp | Ref | Expression | 
						
							| 1 |  | wlkn0 |  |-  ( F ( Walks ` G ) P -> P =/= (/) ) | 
						
							| 2 |  | eqid |  |-  ( Vtx ` G ) = ( Vtx ` G ) | 
						
							| 3 |  | eqid |  |-  ( iEdg ` G ) = ( iEdg ` G ) | 
						
							| 4 | 2 3 | upgriswlk |  |-  ( G e. UPGraph -> ( F ( Walks ` G ) P <-> ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) ) | 
						
							| 5 |  | simpr |  |-  ( ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) /\ P =/= (/) ) -> P =/= (/) ) | 
						
							| 6 |  | ffz0iswrd |  |-  ( P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) -> P e. Word ( Vtx ` G ) ) | 
						
							| 7 | 6 | 3ad2ant2 |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) -> P e. Word ( Vtx ` G ) ) | 
						
							| 8 | 7 | ad2antlr |  |-  ( ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) /\ P =/= (/) ) -> P e. Word ( Vtx ` G ) ) | 
						
							| 9 |  | upgruhgr |  |-  ( G e. UPGraph -> G e. UHGraph ) | 
						
							| 10 | 3 | uhgrfun |  |-  ( G e. UHGraph -> Fun ( iEdg ` G ) ) | 
						
							| 11 |  | funfn |  |-  ( Fun ( iEdg ` G ) <-> ( iEdg ` G ) Fn dom ( iEdg ` G ) ) | 
						
							| 12 | 11 | biimpi |  |-  ( Fun ( iEdg ` G ) -> ( iEdg ` G ) Fn dom ( iEdg ` G ) ) | 
						
							| 13 | 9 10 12 | 3syl |  |-  ( G e. UPGraph -> ( iEdg ` G ) Fn dom ( iEdg ` G ) ) | 
						
							| 14 | 13 | ad2antlr |  |-  ( ( ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) /\ G e. UPGraph ) /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( iEdg ` G ) Fn dom ( iEdg ` G ) ) | 
						
							| 15 |  | wrdsymbcl |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( F ` i ) e. dom ( iEdg ` G ) ) | 
						
							| 16 | 15 | ad4ant14 |  |-  ( ( ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) /\ G e. UPGraph ) /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( F ` i ) e. dom ( iEdg ` G ) ) | 
						
							| 17 |  | fnfvelrn |  |-  ( ( ( iEdg ` G ) Fn dom ( iEdg ` G ) /\ ( F ` i ) e. dom ( iEdg ` G ) ) -> ( ( iEdg ` G ) ` ( F ` i ) ) e. ran ( iEdg ` G ) ) | 
						
							| 18 | 14 16 17 | syl2anc |  |-  ( ( ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) /\ G e. UPGraph ) /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( ( iEdg ` G ) ` ( F ` i ) ) e. ran ( iEdg ` G ) ) | 
						
							| 19 |  | edgval |  |-  ( Edg ` G ) = ran ( iEdg ` G ) | 
						
							| 20 | 18 19 | eleqtrrdi |  |-  ( ( ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) /\ G e. UPGraph ) /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( ( iEdg ` G ) ` ( F ` i ) ) e. ( Edg ` G ) ) | 
						
							| 21 |  | eleq1 |  |-  ( { ( P ` i ) , ( P ` ( i + 1 ) ) } = ( ( iEdg ` G ) ` ( F ` i ) ) -> ( { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) <-> ( ( iEdg ` G ) ` ( F ` i ) ) e. ( Edg ` G ) ) ) | 
						
							| 22 | 21 | eqcoms |  |-  ( ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } -> ( { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) <-> ( ( iEdg ` G ) ` ( F ` i ) ) e. ( Edg ` G ) ) ) | 
						
							| 23 | 20 22 | syl5ibrcom |  |-  ( ( ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) /\ G e. UPGraph ) /\ i e. ( 0 ..^ ( # ` F ) ) ) -> ( ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } -> { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 24 | 23 | ralimdva |  |-  ( ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) /\ G e. UPGraph ) -> ( A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } -> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 25 | 24 | ex |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) -> ( G e. UPGraph -> ( A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } -> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) ) | 
						
							| 26 | 25 | com23 |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) -> ( A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } -> ( G e. UPGraph -> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) ) | 
						
							| 27 | 26 | 3impia |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) -> ( G e. UPGraph -> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 28 | 27 | impcom |  |-  ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) -> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) | 
						
							| 29 |  | lencl |  |-  ( F e. Word dom ( iEdg ` G ) -> ( # ` F ) e. NN0 ) | 
						
							| 30 |  | ffz0hash |  |-  ( ( ( # ` F ) e. NN0 /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) -> ( # ` P ) = ( ( # ` F ) + 1 ) ) | 
						
							| 31 | 30 | ex |  |-  ( ( # ` F ) e. NN0 -> ( P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) -> ( # ` P ) = ( ( # ` F ) + 1 ) ) ) | 
						
							| 32 |  | oveq1 |  |-  ( ( # ` P ) = ( ( # ` F ) + 1 ) -> ( ( # ` P ) - 1 ) = ( ( ( # ` F ) + 1 ) - 1 ) ) | 
						
							| 33 |  | nn0cn |  |-  ( ( # ` F ) e. NN0 -> ( # ` F ) e. CC ) | 
						
							| 34 |  | pncan1 |  |-  ( ( # ` F ) e. CC -> ( ( ( # ` F ) + 1 ) - 1 ) = ( # ` F ) ) | 
						
							| 35 | 33 34 | syl |  |-  ( ( # ` F ) e. NN0 -> ( ( ( # ` F ) + 1 ) - 1 ) = ( # ` F ) ) | 
						
							| 36 | 32 35 | sylan9eqr |  |-  ( ( ( # ` F ) e. NN0 /\ ( # ` P ) = ( ( # ` F ) + 1 ) ) -> ( ( # ` P ) - 1 ) = ( # ` F ) ) | 
						
							| 37 | 36 | ex |  |-  ( ( # ` F ) e. NN0 -> ( ( # ` P ) = ( ( # ` F ) + 1 ) -> ( ( # ` P ) - 1 ) = ( # ` F ) ) ) | 
						
							| 38 | 31 37 | syld |  |-  ( ( # ` F ) e. NN0 -> ( P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) -> ( ( # ` P ) - 1 ) = ( # ` F ) ) ) | 
						
							| 39 | 29 38 | syl |  |-  ( F e. Word dom ( iEdg ` G ) -> ( P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) -> ( ( # ` P ) - 1 ) = ( # ` F ) ) ) | 
						
							| 40 | 39 | imp |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) -> ( ( # ` P ) - 1 ) = ( # ` F ) ) | 
						
							| 41 | 40 | oveq2d |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) -> ( 0 ..^ ( ( # ` P ) - 1 ) ) = ( 0 ..^ ( # ` F ) ) ) | 
						
							| 42 | 41 | raleqdv |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) ) -> ( A. i e. ( 0 ..^ ( ( # ` P ) - 1 ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) <-> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 43 | 42 | 3adant3 |  |-  ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) -> ( A. i e. ( 0 ..^ ( ( # ` P ) - 1 ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) <-> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 44 | 43 | adantl |  |-  ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) -> ( A. i e. ( 0 ..^ ( ( # ` P ) - 1 ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) <-> A. i e. ( 0 ..^ ( # ` F ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 45 | 28 44 | mpbird |  |-  ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) -> A. i e. ( 0 ..^ ( ( # ` P ) - 1 ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) | 
						
							| 46 | 45 | adantr |  |-  ( ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) /\ P =/= (/) ) -> A. i e. ( 0 ..^ ( ( # ` P ) - 1 ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) | 
						
							| 47 |  | eqid |  |-  ( Edg ` G ) = ( Edg ` G ) | 
						
							| 48 | 2 47 | iswwlks |  |-  ( P e. ( WWalks ` G ) <-> ( P =/= (/) /\ P e. Word ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( ( # ` P ) - 1 ) ) { ( P ` i ) , ( P ` ( i + 1 ) ) } e. ( Edg ` G ) ) ) | 
						
							| 49 | 5 8 46 48 | syl3anbrc |  |-  ( ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) /\ P =/= (/) ) -> P e. ( WWalks ` G ) ) | 
						
							| 50 | 49 | ex |  |-  ( ( G e. UPGraph /\ ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) ) -> ( P =/= (/) -> P e. ( WWalks ` G ) ) ) | 
						
							| 51 | 50 | ex |  |-  ( G e. UPGraph -> ( ( F e. Word dom ( iEdg ` G ) /\ P : ( 0 ... ( # ` F ) ) --> ( Vtx ` G ) /\ A. i e. ( 0 ..^ ( # ` F ) ) ( ( iEdg ` G ) ` ( F ` i ) ) = { ( P ` i ) , ( P ` ( i + 1 ) ) } ) -> ( P =/= (/) -> P e. ( WWalks ` G ) ) ) ) | 
						
							| 52 | 4 51 | sylbid |  |-  ( G e. UPGraph -> ( F ( Walks ` G ) P -> ( P =/= (/) -> P e. ( WWalks ` G ) ) ) ) | 
						
							| 53 | 1 52 | mpdi |  |-  ( G e. UPGraph -> ( F ( Walks ` G ) P -> P e. ( WWalks ` G ) ) ) |