| Step | Hyp | Ref | Expression | 
						
							| 1 |  | wlkcl |  |-  ( F ( Walks ` G ) P -> ( # ` F ) e. NN0 ) | 
						
							| 2 | 1 | adantr |  |-  ( ( F ( Walks ` G ) P /\ ( # ` F ) = N ) -> ( # ` F ) e. NN0 ) | 
						
							| 3 |  | wlkiswwlks1 |  |-  ( G e. UPGraph -> ( F ( Walks ` G ) P -> P e. ( WWalks ` G ) ) ) | 
						
							| 4 | 3 | com12 |  |-  ( F ( Walks ` G ) P -> ( G e. UPGraph -> P e. ( WWalks ` G ) ) ) | 
						
							| 5 | 4 | ad2antrl |  |-  ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) -> ( G e. UPGraph -> P e. ( WWalks ` G ) ) ) | 
						
							| 6 | 5 | imp |  |-  ( ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) /\ G e. UPGraph ) -> P e. ( WWalks ` G ) ) | 
						
							| 7 |  | wlklenvp1 |  |-  ( F ( Walks ` G ) P -> ( # ` P ) = ( ( # ` F ) + 1 ) ) | 
						
							| 8 | 7 | ad2antrl |  |-  ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) -> ( # ` P ) = ( ( # ` F ) + 1 ) ) | 
						
							| 9 |  | oveq1 |  |-  ( ( # ` F ) = N -> ( ( # ` F ) + 1 ) = ( N + 1 ) ) | 
						
							| 10 | 9 | adantl |  |-  ( ( F ( Walks ` G ) P /\ ( # ` F ) = N ) -> ( ( # ` F ) + 1 ) = ( N + 1 ) ) | 
						
							| 11 | 10 | adantl |  |-  ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) -> ( ( # ` F ) + 1 ) = ( N + 1 ) ) | 
						
							| 12 | 8 11 | eqtrd |  |-  ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) -> ( # ` P ) = ( N + 1 ) ) | 
						
							| 13 | 12 | adantr |  |-  ( ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) /\ G e. UPGraph ) -> ( # ` P ) = ( N + 1 ) ) | 
						
							| 14 |  | eleq1 |  |-  ( ( # ` F ) = N -> ( ( # ` F ) e. NN0 <-> N e. NN0 ) ) | 
						
							| 15 |  | iswwlksn |  |-  ( N e. NN0 -> ( P e. ( N WWalksN G ) <-> ( P e. ( WWalks ` G ) /\ ( # ` P ) = ( N + 1 ) ) ) ) | 
						
							| 16 | 14 15 | biimtrdi |  |-  ( ( # ` F ) = N -> ( ( # ` F ) e. NN0 -> ( P e. ( N WWalksN G ) <-> ( P e. ( WWalks ` G ) /\ ( # ` P ) = ( N + 1 ) ) ) ) ) | 
						
							| 17 | 16 | adantl |  |-  ( ( F ( Walks ` G ) P /\ ( # ` F ) = N ) -> ( ( # ` F ) e. NN0 -> ( P e. ( N WWalksN G ) <-> ( P e. ( WWalks ` G ) /\ ( # ` P ) = ( N + 1 ) ) ) ) ) | 
						
							| 18 | 17 | impcom |  |-  ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) -> ( P e. ( N WWalksN G ) <-> ( P e. ( WWalks ` G ) /\ ( # ` P ) = ( N + 1 ) ) ) ) | 
						
							| 19 | 18 | adantr |  |-  ( ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) /\ G e. UPGraph ) -> ( P e. ( N WWalksN G ) <-> ( P e. ( WWalks ` G ) /\ ( # ` P ) = ( N + 1 ) ) ) ) | 
						
							| 20 | 6 13 19 | mpbir2and |  |-  ( ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) /\ G e. UPGraph ) -> P e. ( N WWalksN G ) ) | 
						
							| 21 | 20 | ex |  |-  ( ( ( # ` F ) e. NN0 /\ ( F ( Walks ` G ) P /\ ( # ` F ) = N ) ) -> ( G e. UPGraph -> P e. ( N WWalksN G ) ) ) | 
						
							| 22 | 2 21 | mpancom |  |-  ( ( F ( Walks ` G ) P /\ ( # ` F ) = N ) -> ( G e. UPGraph -> P e. ( N WWalksN G ) ) ) | 
						
							| 23 | 22 | com12 |  |-  ( G e. UPGraph -> ( ( F ( Walks ` G ) P /\ ( # ` F ) = N ) -> P e. ( N WWalksN G ) ) ) |