| Step | Hyp | Ref | Expression | 
						
							| 1 |  | efgval.w | ⊢ 𝑊  =  (  I  ‘ Word  ( 𝐼  ×  2o ) ) | 
						
							| 2 |  | efgval.r | ⊢  ∼   =  (  ~FG  ‘ 𝐼 ) | 
						
							| 3 |  | efgval2.m | ⊢ 𝑀  =  ( 𝑦  ∈  𝐼 ,  𝑧  ∈  2o  ↦  〈 𝑦 ,  ( 1o  ∖  𝑧 ) 〉 ) | 
						
							| 4 |  | efgval2.t | ⊢ 𝑇  =  ( 𝑣  ∈  𝑊  ↦  ( 𝑛  ∈  ( 0 ... ( ♯ ‘ 𝑣 ) ) ,  𝑤  ∈  ( 𝐼  ×  2o )  ↦  ( 𝑣  splice  〈 𝑛 ,  𝑛 ,  〈“ 𝑤 ( 𝑀 ‘ 𝑤 ) ”〉 〉 ) ) ) | 
						
							| 5 |  | efgred.d | ⊢ 𝐷  =  ( 𝑊  ∖  ∪  𝑥  ∈  𝑊 ran  ( 𝑇 ‘ 𝑥 ) ) | 
						
							| 6 |  | efgred.s | ⊢ 𝑆  =  ( 𝑚  ∈  { 𝑡  ∈  ( Word  𝑊  ∖  { ∅ } )  ∣  ( ( 𝑡 ‘ 0 )  ∈  𝐷  ∧  ∀ 𝑘  ∈  ( 1 ..^ ( ♯ ‘ 𝑡 ) ) ( 𝑡 ‘ 𝑘 )  ∈  ran  ( 𝑇 ‘ ( 𝑡 ‘ ( 𝑘  −  1 ) ) ) ) }  ↦  ( 𝑚 ‘ ( ( ♯ ‘ 𝑚 )  −  1 ) ) ) | 
						
							| 7 | 1 2 3 4 5 6 | efgsfo | ⊢ 𝑆 : dom  𝑆 –onto→ 𝑊 | 
						
							| 8 |  | fof | ⊢ ( 𝑆 : dom  𝑆 –onto→ 𝑊  →  𝑆 : dom  𝑆 ⟶ 𝑊 ) | 
						
							| 9 | 7 8 | ax-mp | ⊢ 𝑆 : dom  𝑆 ⟶ 𝑊 | 
						
							| 10 | 9 | ffvelcdmi | ⊢ ( 𝐵  ∈  dom  𝑆  →  ( 𝑆 ‘ 𝐵 )  ∈  𝑊 ) | 
						
							| 11 | 10 | ad2antlr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝑆 ‘ 𝐵 )  ∈  𝑊 ) | 
						
							| 12 | 1 2 3 4 5 6 | efgredeu | ⊢ ( ( 𝑆 ‘ 𝐵 )  ∈  𝑊  →  ∃! 𝑑  ∈  𝐷 𝑑  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 13 |  | reurmo | ⊢ ( ∃! 𝑑  ∈  𝐷 𝑑  ∼  ( 𝑆 ‘ 𝐵 )  →  ∃* 𝑑  ∈  𝐷 𝑑  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 14 | 11 12 13 | 3syl | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ∃* 𝑑  ∈  𝐷 𝑑  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 15 | 1 2 3 4 5 6 | efgsdm | ⊢ ( 𝐴  ∈  dom  𝑆  ↔  ( 𝐴  ∈  ( Word  𝑊  ∖  { ∅ } )  ∧  ( 𝐴 ‘ 0 )  ∈  𝐷  ∧  ∀ 𝑖  ∈  ( 1 ..^ ( ♯ ‘ 𝐴 ) ) ( 𝐴 ‘ 𝑖 )  ∈  ran  ( 𝑇 ‘ ( 𝐴 ‘ ( 𝑖  −  1 ) ) ) ) ) | 
						
							| 16 | 15 | simp2bi | ⊢ ( 𝐴  ∈  dom  𝑆  →  ( 𝐴 ‘ 0 )  ∈  𝐷 ) | 
						
							| 17 | 16 | ad2antrr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐴 ‘ 0 )  ∈  𝐷 ) | 
						
							| 18 | 1 2 | efger | ⊢  ∼   Er  𝑊 | 
						
							| 19 | 18 | a1i | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →   ∼   Er  𝑊 ) | 
						
							| 20 | 1 2 3 4 5 6 | efgsrel | ⊢ ( 𝐴  ∈  dom  𝑆  →  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐴 ) ) | 
						
							| 21 | 20 | ad2antrr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐴 ) ) | 
						
							| 22 |  | simpr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 23 | 19 21 22 | ertrd | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 24 | 1 2 3 4 5 6 | efgsdm | ⊢ ( 𝐵  ∈  dom  𝑆  ↔  ( 𝐵  ∈  ( Word  𝑊  ∖  { ∅ } )  ∧  ( 𝐵 ‘ 0 )  ∈  𝐷  ∧  ∀ 𝑖  ∈  ( 1 ..^ ( ♯ ‘ 𝐵 ) ) ( 𝐵 ‘ 𝑖 )  ∈  ran  ( 𝑇 ‘ ( 𝐵 ‘ ( 𝑖  −  1 ) ) ) ) ) | 
						
							| 25 | 24 | simp2bi | ⊢ ( 𝐵  ∈  dom  𝑆  →  ( 𝐵 ‘ 0 )  ∈  𝐷 ) | 
						
							| 26 | 25 | ad2antlr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐵 ‘ 0 )  ∈  𝐷 ) | 
						
							| 27 | 1 2 3 4 5 6 | efgsrel | ⊢ ( 𝐵  ∈  dom  𝑆  →  ( 𝐵 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 28 | 27 | ad2antlr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐵 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 29 |  | breq1 | ⊢ ( 𝑑  =  ( 𝐴 ‘ 0 )  →  ( 𝑑  ∼  ( 𝑆 ‘ 𝐵 )  ↔  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) ) | 
						
							| 30 |  | breq1 | ⊢ ( 𝑑  =  ( 𝐵 ‘ 0 )  →  ( 𝑑  ∼  ( 𝑆 ‘ 𝐵 )  ↔  ( 𝐵 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) ) | 
						
							| 31 | 29 30 | rmoi | ⊢ ( ( ∃* 𝑑  ∈  𝐷 𝑑  ∼  ( 𝑆 ‘ 𝐵 )  ∧  ( ( 𝐴 ‘ 0 )  ∈  𝐷  ∧  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) )  ∧  ( ( 𝐵 ‘ 0 )  ∈  𝐷  ∧  ( 𝐵 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) | 
						
							| 32 | 14 17 23 26 28 31 | syl122anc | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) | 
						
							| 33 | 18 | a1i | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) )  →   ∼   Er  𝑊 ) | 
						
							| 34 | 20 | ad2antrr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) )  →  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐴 ) ) | 
						
							| 35 |  | simpr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) | 
						
							| 36 | 27 | ad2antlr | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) )  →  ( 𝐵 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 37 | 35 36 | eqbrtrd | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) )  →  ( 𝐴 ‘ 0 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 38 | 33 34 37 | ertr3d | ⊢ ( ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  ∧  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) )  →  ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 39 | 32 38 | impbida | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ( 𝑆 ‘ 𝐴 )  ∼  ( 𝑆 ‘ 𝐵 )  ↔  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) ) |