| Step | Hyp | Ref | Expression | 
						
							| 1 |  | f1fn | ⊢ ( 𝐸 : dom  𝐸 –1-1→ 𝑅  →  𝐸  Fn  dom  𝐸 ) | 
						
							| 2 |  | dffn3 | ⊢ ( 𝐸  Fn  dom  𝐸  ↔  𝐸 : dom  𝐸 ⟶ ran  𝐸 ) | 
						
							| 3 | 1 2 | sylib | ⊢ ( 𝐸 : dom  𝐸 –1-1→ 𝑅  →  𝐸 : dom  𝐸 ⟶ ran  𝐸 ) | 
						
							| 4 |  | lencl | ⊢ ( 𝐹  ∈  Word  dom  𝐸  →  ( ♯ ‘ 𝐹 )  ∈  ℕ0 ) | 
						
							| 5 |  | ffn | ⊢ ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  𝑃  Fn  ( 0 ... ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 6 |  | fnfz0hash | ⊢ ( ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  ∧  𝑃  Fn  ( 0 ... ( ♯ ‘ 𝐹 ) ) )  →  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) ) | 
						
							| 7 | 4 5 6 | syl2an | ⊢ ( ( 𝐹  ∈  Word  dom  𝐸  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉 )  →  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) ) | 
						
							| 8 |  | ffz0iswrd | ⊢ ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  𝑃  ∈  Word  𝑉 ) | 
						
							| 9 |  | lsw | ⊢ ( 𝑃  ∈  Word  𝑉  →  ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ ( ( ♯ ‘ 𝑃 )  −  1 ) ) ) | 
						
							| 10 | 9 | ad6antr | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ ( ( ♯ ‘ 𝑃 )  −  1 ) ) ) | 
						
							| 11 |  | fvoveq1 | ⊢ ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 𝑃 ‘ ( ( ♯ ‘ 𝑃 )  −  1 ) )  =  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) ) ) | 
						
							| 12 | 11 | ad4antlr | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( 𝑃 ‘ ( ( ♯ ‘ 𝑃 )  −  1 ) )  =  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) ) ) | 
						
							| 13 |  | eqcom | ⊢ ( ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  ↔  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  =  ( 𝑃 ‘ 0 ) ) | 
						
							| 14 |  | nn0cn | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ℂ ) | 
						
							| 15 |  | 1cnd | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  1  ∈  ℂ ) | 
						
							| 16 | 14 15 | pncand | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 17 | 16 | eqcomd | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  =  ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) ) | 
						
							| 18 | 17 | ad4antlr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ♯ ‘ 𝐹 )  =  ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) ) | 
						
							| 19 | 18 | fveqeq2d | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  =  ( 𝑃 ‘ 0 )  ↔  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) )  =  ( 𝑃 ‘ 0 ) ) ) | 
						
							| 20 | 19 | biimpd | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  =  ( 𝑃 ‘ 0 )  →  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) )  =  ( 𝑃 ‘ 0 ) ) ) | 
						
							| 21 | 13 20 | biimtrid | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  →  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) )  =  ( 𝑃 ‘ 0 ) ) ) | 
						
							| 22 | 21 | adantld | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) )  =  ( 𝑃 ‘ 0 ) ) ) | 
						
							| 23 | 22 | imp | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  +  1 )  −  1 ) )  =  ( 𝑃 ‘ 0 ) ) | 
						
							| 24 | 10 12 23 | 3eqtrd | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 ) ) | 
						
							| 25 |  | nn0z | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ℤ ) | 
						
							| 26 |  | peano2zm | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℤ  →  ( ( ♯ ‘ 𝐹 )  −  1 )  ∈  ℤ ) | 
						
							| 27 | 25 26 | syl | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ♯ ‘ 𝐹 )  −  1 )  ∈  ℤ ) | 
						
							| 28 |  | nn0re | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ℝ ) | 
						
							| 29 | 28 | lem1d | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ♯ ‘ 𝐹 )  −  1 )  ≤  ( ♯ ‘ 𝐹 ) ) | 
						
							| 30 |  | eluz2 | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ↔  ( ( ( ♯ ‘ 𝐹 )  −  1 )  ∈  ℤ  ∧  ( ♯ ‘ 𝐹 )  ∈  ℤ  ∧  ( ( ♯ ‘ 𝐹 )  −  1 )  ≤  ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 31 | 27 25 29 30 | syl3anbrc | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ) | 
						
							| 32 | 31 | ad4antlr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ♯ ‘ 𝐹 )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ) | 
						
							| 33 |  | fzoss2 | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ⊆  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 34 |  | ssralv | ⊢ ( ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ⊆  ( 0 ..^ ( ♯ ‘ 𝐹 ) )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) ) | 
						
							| 35 | 32 33 34 | 3syl | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) } ) ) | 
						
							| 36 |  | simpr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  𝐸 : dom  𝐸 ⟶ ran  𝐸 ) | 
						
							| 37 | 36 | adantr | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  𝐸 : dom  𝐸 ⟶ ran  𝐸 ) | 
						
							| 38 |  | wrdf | ⊢ ( 𝐹  ∈  Word  dom  𝐸  →  𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸 ) | 
						
							| 39 |  | simpll | ⊢ ( ( ( 𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸 ) | 
						
							| 40 |  | fzossrbm1 | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℤ  →  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ⊆  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 41 | 25 40 | syl | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ⊆  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 42 | 41 | adantl | ⊢ ( ( 𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  →  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ⊆  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 43 | 42 | sselda | ⊢ ( ( ( 𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 44 | 39 43 | ffvelcdmd | ⊢ ( ( ( 𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) | 
						
							| 45 | 44 | exp31 | ⊢ ( 𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) ) ) | 
						
							| 46 | 38 45 | syl | ⊢ ( 𝐹  ∈  Word  dom  𝐸  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) ) ) | 
						
							| 47 | 46 | adantl | ⊢ ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) ) ) | 
						
							| 48 | 47 | imp | ⊢ ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  →  ( 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) ) | 
						
							| 49 | 48 | ad3antrrr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) ) | 
						
							| 50 | 49 | imp | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  ( 𝐹 ‘ 𝑖 )  ∈  dom  𝐸 ) | 
						
							| 51 | 37 50 | ffvelcdmd | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ran  𝐸 ) | 
						
							| 52 |  | eqcom | ⊢ ( ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ↔  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  =  ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) ) ) | 
						
							| 53 | 52 | biimpi | ⊢ ( ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  =  ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) ) ) | 
						
							| 54 | 53 | eleq1d | ⊢ ( ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ( { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ↔  ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  ∈  ran  𝐸 ) ) | 
						
							| 55 | 51 54 | syl5ibrcom | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  →  ( ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 56 | 55 | ralimdva | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 57 | 35 56 | syldc | ⊢ ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 58 | 57 | adantr | ⊢ ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 59 | 58 | impcom | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸 ) | 
						
							| 60 |  | breq2 | ⊢ ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  ↔  2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 ) ) ) | 
						
							| 61 | 60 | adantl | ⊢ ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  ↔  2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 ) ) ) | 
						
							| 62 |  | 2re | ⊢ 2  ∈  ℝ | 
						
							| 63 | 62 | a1i | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  2  ∈  ℝ ) | 
						
							| 64 |  | 1red | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  1  ∈  ℝ ) | 
						
							| 65 | 63 64 28 | lesubaddd | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( 2  −  1 )  ≤  ( ♯ ‘ 𝐹 )  ↔  2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 ) ) ) | 
						
							| 66 |  | 2m1e1 | ⊢ ( 2  −  1 )  =  1 | 
						
							| 67 | 66 | breq1i | ⊢ ( ( 2  −  1 )  ≤  ( ♯ ‘ 𝐹 )  ↔  1  ≤  ( ♯ ‘ 𝐹 ) ) | 
						
							| 68 |  | elnnnn0c | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ  ↔  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  ∧  1  ≤  ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 69 | 68 | simplbi2 | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 1  ≤  ( ♯ ‘ 𝐹 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 70 | 67 69 | biimtrid | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( 2  −  1 )  ≤  ( ♯ ‘ 𝐹 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 71 | 65 70 | sylbird | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 72 | 71 | adantl | ⊢ ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  →  ( 2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 73 | 72 | adantr | ⊢ ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  →  ( 2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 74 | 61 73 | sylbid | ⊢ ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 75 | 74 | imp | ⊢ ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) | 
						
							| 76 | 75 | adantr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) | 
						
							| 77 |  | lbfzo0 | ⊢ ( 0  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) )  ↔  ( ♯ ‘ 𝐹 )  ∈  ℕ ) | 
						
							| 78 | 76 77 | sylibr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  0  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 79 |  | fzoend | ⊢ ( 0  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) )  →  ( ( ♯ ‘ 𝐹 )  −  1 )  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 80 | 78 79 | syl | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( ♯ ‘ 𝐹 )  −  1 )  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 81 |  | 2fveq3 | ⊢ ( 𝑖  =  ( ( ♯ ‘ 𝐹 )  −  1 )  →  ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ) ) | 
						
							| 82 |  | fveq2 | ⊢ ( 𝑖  =  ( ( ♯ ‘ 𝐹 )  −  1 )  →  ( 𝑃 ‘ 𝑖 )  =  ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ) | 
						
							| 83 |  | fvoveq1 | ⊢ ( 𝑖  =  ( ( ♯ ‘ 𝐹 )  −  1 )  →  ( 𝑃 ‘ ( 𝑖  +  1 ) )  =  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) ) | 
						
							| 84 | 82 83 | preq12d | ⊢ ( 𝑖  =  ( ( ♯ ‘ 𝐹 )  −  1 )  →  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) } ) | 
						
							| 85 | 81 84 | eqeq12d | ⊢ ( 𝑖  =  ( ( ♯ ‘ 𝐹 )  −  1 )  →  ( ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ↔  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) } ) ) | 
						
							| 86 | 85 | adantl | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  𝑖  =  ( ( ♯ ‘ 𝐹 )  −  1 ) )  →  ( ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ↔  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) } ) ) | 
						
							| 87 | 80 86 | rspcdv | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) } ) ) | 
						
							| 88 | 14 15 | npcand | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 89 | 88 | ad4antlr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 )  =  ( ♯ ‘ 𝐹 ) ) | 
						
							| 90 | 89 | fveq2d | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 91 | 90 | preq2d | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) }  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) } ) | 
						
							| 92 | 91 | eqeq2d | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) }  ↔  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) } ) ) | 
						
							| 93 | 38 | ad4antlr | ⊢ ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  𝐹 : ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ⟶ dom  𝐸 ) | 
						
							| 94 | 71 | com12 | ⊢ ( 2  ≤  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) | 
						
							| 95 | 60 94 | biimtrdi | ⊢ ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) ) | 
						
							| 96 | 95 | com3r | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) ) | 
						
							| 97 | 96 | adantl | ⊢ ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) ) ) | 
						
							| 98 | 97 | imp31 | ⊢ ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  ( ♯ ‘ 𝐹 )  ∈  ℕ ) | 
						
							| 99 | 98 77 | sylibr | ⊢ ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  0  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 100 | 99 79 | syl | ⊢ ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  ( ( ♯ ‘ 𝐹 )  −  1 )  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ) | 
						
							| 101 | 93 100 | ffvelcdmd | ⊢ ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ∈  dom  𝐸 ) | 
						
							| 102 | 101 | adantr | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) )  ∈  dom  𝐸 ) | 
						
							| 103 | 36 102 | ffvelcdmd | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  ∈  ran  𝐸 ) | 
						
							| 104 |  | eqcom | ⊢ ( ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ↔  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  =  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ) ) | 
						
							| 105 | 104 | biimpi | ⊢ ( ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  =  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ) ) | 
						
							| 106 | 105 | eleq1d | ⊢ ( ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  →  ( { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸  ↔  ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  ∈  ran  𝐸 ) ) | 
						
							| 107 | 103 106 | syl5ibrcom | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 108 | 92 107 | sylbid | ⊢ ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  ( ( 𝐸 ‘ ( 𝐹 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) )  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ( ( ♯ ‘ 𝐹 )  −  1 )  +  1 ) ) }  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 109 | 87 108 | syldc | ⊢ ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  →  ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 110 | 109 | adantr | ⊢ ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 111 | 110 | impcom | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) | 
						
							| 112 |  | preq2 | ⊢ ( ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  =  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) } ) | 
						
							| 113 | 112 | eleq1d | ⊢ ( ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) )  →  ( { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸  ↔  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 114 | 113 | adantl | ⊢ ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸  ↔  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 115 | 114 | adantl | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸  ↔  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) }  ∈  ran  𝐸 ) ) | 
						
							| 116 | 111 115 | mpbird | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) | 
						
							| 117 | 24 59 116 | 3jca | ⊢ ( ( ( ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  𝐸 : dom  𝐸 ⟶ ran  𝐸 )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) | 
						
							| 118 | 117 | exp41 | ⊢ ( ( ( ( 𝑃  ∈  Word  𝑉  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( ♯ ‘ 𝐹 )  ∈  ℕ0 )  ∧  ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 ) )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) | 
						
							| 119 | 118 | exp41 | ⊢ ( 𝑃  ∈  Word  𝑉  →  ( 𝐹  ∈  Word  dom  𝐸  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) ) ) | 
						
							| 120 | 8 119 | syl | ⊢ ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  ( 𝐹  ∈  Word  dom  𝐸  →  ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) ) ) | 
						
							| 121 | 120 | com13 | ⊢ ( ( ♯ ‘ 𝐹 )  ∈  ℕ0  →  ( 𝐹  ∈  Word  dom  𝐸  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) ) ) | 
						
							| 122 | 4 121 | mpcom | ⊢ ( 𝐹  ∈  Word  dom  𝐸  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) ) | 
						
							| 123 | 122 | imp | ⊢ ( ( 𝐹  ∈  Word  dom  𝐸  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉 )  →  ( ( ♯ ‘ 𝑃 )  =  ( ( ♯ ‘ 𝐹 )  +  1 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) | 
						
							| 124 | 7 123 | mpd | ⊢ ( ( 𝐹  ∈  Word  dom  𝐸  ∧  𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) | 
						
							| 125 | 124 | expcom | ⊢ ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  ( 𝐹  ∈  Word  dom  𝐸  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) | 
						
							| 126 | 125 | com14 | ⊢ ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  →  ( 𝐹  ∈  Word  dom  𝐸  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) ) | 
						
							| 127 | 126 | imp | ⊢ ( ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  ∧  𝐹  ∈  Word  dom  𝐸 )  →  ( 2  ≤  ( ♯ ‘ 𝑃 )  →  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) ) | 
						
							| 128 | 127 | impcomd | ⊢ ( ( 𝐸 : dom  𝐸 ⟶ ran  𝐸  ∧  𝐹  ∈  Word  dom  𝐸 )  →  ( ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) | 
						
							| 129 | 3 128 | sylan | ⊢ ( ( 𝐸 : dom  𝐸 –1-1→ 𝑅  ∧  𝐹  ∈  Word  dom  𝐸 )  →  ( ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  →  ( ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) ) ) | 
						
							| 130 | 129 | 3imp | ⊢ ( ( ( 𝐸 : dom  𝐸 –1-1→ 𝑅  ∧  𝐹  ∈  Word  dom  𝐸 )  ∧  ( 𝑃 : ( 0 ... ( ♯ ‘ 𝐹 ) ) ⟶ 𝑉  ∧  2  ≤  ( ♯ ‘ 𝑃 ) )  ∧  ( ∀ 𝑖  ∈  ( 0 ..^ ( ♯ ‘ 𝐹 ) ) ( 𝐸 ‘ ( 𝐹 ‘ 𝑖 ) )  =  { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∧  ( 𝑃 ‘ 0 )  =  ( 𝑃 ‘ ( ♯ ‘ 𝐹 ) ) ) )  →  ( ( lastS ‘ 𝑃 )  =  ( 𝑃 ‘ 0 )  ∧  ∀ 𝑖  ∈  ( 0 ..^ ( ( ♯ ‘ 𝐹 )  −  1 ) ) { ( 𝑃 ‘ 𝑖 ) ,  ( 𝑃 ‘ ( 𝑖  +  1 ) ) }  ∈  ran  𝐸  ∧  { ( 𝑃 ‘ ( ( ♯ ‘ 𝐹 )  −  1 ) ) ,  ( 𝑃 ‘ 0 ) }  ∈  ran  𝐸 ) ) |