| 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  ∈  UPGraph  →  ( 𝐹 ( Walks ‘ 𝐺 ) 𝑃  ↔  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) ) ) | 
						
							| 5 |  | simpr | ⊢ ( ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  ∧  𝑃  ≠  ∅ )  →  𝑃  ≠  ∅ ) | 
						
							| 6 |  | ffz0iswrd | ⊢ ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  →  𝑃  ∈  Word  ( Vtx ‘ 𝐺 ) ) | 
						
							| 7 | 6 | 3ad2ant2 | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } )  →  𝑃  ∈  Word  ( Vtx ‘ 𝐺 ) ) | 
						
							| 8 | 7 | ad2antlr | ⊢ ( ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  ∧  𝑃  ≠  ∅ )  →  𝑃  ∈  Word  ( Vtx ‘ 𝐺 ) ) | 
						
							| 9 |  | upgruhgr | ⊢ ( 𝐺  ∈  UPGraph  →  𝐺  ∈  UHGraph ) | 
						
							| 10 | 3 | uhgrfun | ⊢ ( 𝐺  ∈  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  ∈  UPGraph  →  ( iEdg ‘ 𝐺 )  Fn  dom  ( iEdg ‘ 𝐺 ) ) | 
						
							| 14 | 13 | ad2antlr | ⊢ ( ( ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  ∧  𝐺  ∈  UPGraph )  ∧  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) )  →  ( iEdg ‘ 𝐺 )  Fn  dom  ( iEdg ‘ 𝐺 ) ) | 
						
							| 15 |  | wrdsymbcl | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  ( iEdg ‘ 𝐺 ) ) | 
						
							| 16 | 15 | ad4ant14 | ⊢ ( ( ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  ∧  𝐺  ∈  UPGraph )  ∧  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  ( iEdg ‘ 𝐺 ) ) | 
						
							| 17 |  | fnfvelrn | ⊢ ( ( ( iEdg ‘ 𝐺 )  Fn  dom  ( iEdg ‘ 𝐺 )  ∧  ( 𝐹 ‘ 𝑖 )  ∈  dom  ( iEdg ‘ 𝐺 ) )  →  ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ran  ( iEdg ‘ 𝐺 ) ) | 
						
							| 18 | 14 16 17 | syl2anc | ⊢ ( ( ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  ∧  𝐺  ∈  UPGraph )  ∧  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) )  →  ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ran  ( iEdg ‘ 𝐺 ) ) | 
						
							| 19 |  | edgval | ⊢ ( Edg ‘ 𝐺 )  =  ran  ( iEdg ‘ 𝐺 ) | 
						
							| 20 | 18 19 | eleqtrrdi | ⊢ ( ( ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  ∧  𝐺  ∈  UPGraph )  ∧  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) )  →  ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ( Edg ‘ 𝐺 ) ) | 
						
							| 21 |  | eleq1 | ⊢ ( { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  =  ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  →  ( { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 )  ↔  ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 22 | 21 | eqcoms | ⊢ ( ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ( { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 )  ↔  ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 23 | 20 22 | syl5ibrcom | ⊢ ( ( ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  ∧  𝐺  ∈  UPGraph )  ∧  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) )  →  ( ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 24 | 23 | ralimdva | ⊢ ( ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  ∧  𝐺  ∈  UPGraph )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 25 | 24 | ex | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  →  ( 𝐺  ∈  UPGraph  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) ) | 
						
							| 26 | 25 | com23 | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ( 𝐺  ∈  UPGraph  →  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) ) | 
						
							| 27 | 26 | 3impia | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } )  →  ( 𝐺  ∈  UPGraph  →  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 28 | 27 | impcom | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  →  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) | 
						
							| 29 |  | lencl | ⊢ ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ0 ) | 
						
							| 30 |  | ffz0hash | ⊢ ( ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  →  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) ) | 
						
							| 31 | 30 | ex | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  →  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) ) ) | 
						
							| 32 |  | oveq1 | ⊢ ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( ( ♯ ‘ 𝑃 )  −  1 )  =  ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) ) | 
						
							| 33 |  | nn0cn | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ℂ ) | 
						
							| 34 |  | pncan1 | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℂ  →  ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 35 | 33 34 | syl | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 36 | 32 35 | sylan9eqr | ⊢ ( ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  →  ( ( ♯ ‘ 𝑃 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 37 | 36 | ex | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( ( ♯ ‘ 𝑃 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 38 | 31 37 | syld | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  →  ( ( ♯ ‘ 𝑃 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 39 | 29 38 | syl | ⊢ ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  →  ( ( ♯ ‘ 𝑃 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 40 | 39 | imp | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  →  ( ( ♯ ‘ 𝑃 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 41 | 40 | oveq2d | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  →  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) )  =  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 42 | 41 | raleqdv | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 ) )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 )  ↔  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 43 | 42 | 3adant3 | ⊢ ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 )  ↔  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 44 | 43 | adantl | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 )  ↔  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 45 | 28 44 | mpbird | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) | 
						
							| 46 | 45 | adantr | ⊢ ( ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  ∧  𝑃  ≠  ∅ )  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) | 
						
							| 47 |  | eqid | ⊢ ( Edg ‘ 𝐺 )  =  ( Edg ‘ 𝐺 ) | 
						
							| 48 | 2 47 | iswwlks | ⊢ ( 𝑃  ∈  ( WWalks ‘ 𝐺 )  ↔  ( 𝑃  ≠  ∅  ∧  𝑃  ∈  Word  ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝑃 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ( Edg ‘ 𝐺 ) ) ) | 
						
							| 49 | 5 8 46 48 | syl3anbrc | ⊢ ( ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  ∧  𝑃  ≠  ∅ )  →  𝑃  ∈  ( WWalks ‘ 𝐺 ) ) | 
						
							| 50 | 49 | ex | ⊢ ( ( 𝐺  ∈  UPGraph  ∧  ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) )  →  ( 𝑃  ≠  ∅  →  𝑃  ∈  ( WWalks ‘ 𝐺 ) ) ) | 
						
							| 51 | 50 | ex | ⊢ ( 𝐺  ∈  UPGraph  →  ( ( 𝐹  ∈  Word  dom  ( iEdg ‘ 𝐺 )  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ ( Vtx ‘ 𝐺 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( ( iEdg ‘ 𝐺 ) ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } )  →  ( 𝑃  ≠  ∅  →  𝑃  ∈  ( WWalks ‘ 𝐺 ) ) ) ) | 
						
							| 52 | 4 51 | sylbid | ⊢ ( 𝐺  ∈  UPGraph  →  ( 𝐹 ( Walks ‘ 𝐺 ) 𝑃  →  ( 𝑃  ≠  ∅  →  𝑃  ∈  ( WWalks ‘ 𝐺 ) ) ) ) | 
						
							| 53 | 1 52 | mpdi | ⊢ ( 𝐺  ∈  UPGraph  →  ( 𝐹 ( Walks ‘ 𝐺 ) 𝑃  →  𝑃  ∈  ( WWalks ‘ 𝐺 ) ) ) |