| 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 |  | fviss | ⊢ (  I  ‘ Word  ( 𝐼  ×  2o ) )  ⊆  Word  ( 𝐼  ×  2o ) | 
						
							| 8 | 1 7 | eqsstri | ⊢ 𝑊  ⊆  Word  ( 𝐼  ×  2o ) | 
						
							| 9 | 1 2 3 4 5 6 | efgsf | ⊢ 𝑆 : { 𝑡  ∈  ( Word  𝑊  ∖  { ∅ } )  ∣  ( ( 𝑡 ‘ 0 )  ∈  𝐷  ∧  ∀ 𝑘  ∈  ( 1 ..^ ( ♯ ‘ 𝑡 ) ) ( 𝑡 ‘ 𝑘 )  ∈  ran  ( 𝑇 ‘ ( 𝑡 ‘ ( 𝑘  −  1 ) ) ) ) } ⟶ 𝑊 | 
						
							| 10 | 9 | fdmi | ⊢ dom  𝑆  =  { 𝑡  ∈  ( Word  𝑊  ∖  { ∅ } )  ∣  ( ( 𝑡 ‘ 0 )  ∈  𝐷  ∧  ∀ 𝑘  ∈  ( 1 ..^ ( ♯ ‘ 𝑡 ) ) ( 𝑡 ‘ 𝑘 )  ∈  ran  ( 𝑇 ‘ ( 𝑡 ‘ ( 𝑘  −  1 ) ) ) ) } | 
						
							| 11 | 10 | feq2i | ⊢ ( 𝑆 : dom  𝑆 ⟶ 𝑊  ↔  𝑆 : { 𝑡  ∈  ( Word  𝑊  ∖  { ∅ } )  ∣  ( ( 𝑡 ‘ 0 )  ∈  𝐷  ∧  ∀ 𝑘  ∈  ( 1 ..^ ( ♯ ‘ 𝑡 ) ) ( 𝑡 ‘ 𝑘 )  ∈  ran  ( 𝑇 ‘ ( 𝑡 ‘ ( 𝑘  −  1 ) ) ) ) } ⟶ 𝑊 ) | 
						
							| 12 | 9 11 | mpbir | ⊢ 𝑆 : dom  𝑆 ⟶ 𝑊 | 
						
							| 13 | 12 | ffvelcdmi | ⊢ ( 𝐴  ∈  dom  𝑆  →  ( 𝑆 ‘ 𝐴 )  ∈  𝑊 ) | 
						
							| 14 | 13 | adantr | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( 𝑆 ‘ 𝐴 )  ∈  𝑊 ) | 
						
							| 15 | 8 14 | sselid | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( 𝑆 ‘ 𝐴 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 16 |  | lencl | ⊢ ( ( 𝑆 ‘ 𝐴 )  ∈  Word  ( 𝐼  ×  2o )  →  ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  ∈  ℕ0 ) | 
						
							| 17 | 15 16 | syl | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  ∈  ℕ0 ) | 
						
							| 18 |  | peano2nn0 | ⊢ ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  ∈  ℕ0  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  ∈  ℕ0 ) | 
						
							| 19 | 17 18 | syl | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  ∈  ℕ0 ) | 
						
							| 20 |  | breq2 | ⊢ ( 𝑐  =  0  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0 ) ) | 
						
							| 21 | 20 | imbi1d | ⊢ ( 𝑐  =  0  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 22 | 21 | 2ralbidv | ⊢ ( 𝑐  =  0  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 23 |  | breq2 | ⊢ ( 𝑐  =  𝑖  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖 ) ) | 
						
							| 24 | 23 | imbi1d | ⊢ ( 𝑐  =  𝑖  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 25 | 24 | 2ralbidv | ⊢ ( 𝑐  =  𝑖  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 26 |  | breq2 | ⊢ ( 𝑐  =  ( 𝑖  +  1 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 ) ) ) | 
						
							| 27 | 26 | imbi1d | ⊢ ( 𝑐  =  ( 𝑖  +  1 )  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 28 | 27 | 2ralbidv | ⊢ ( 𝑐  =  ( 𝑖  +  1 )  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 29 |  | breq2 | ⊢ ( 𝑐  =  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 ) ) ) | 
						
							| 30 | 29 | imbi1d | ⊢ ( 𝑐  =  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 31 | 30 | 2ralbidv | ⊢ ( 𝑐  =  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑐  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 32 | 12 | ffvelcdmi | ⊢ ( 𝑎  ∈  dom  𝑆  →  ( 𝑆 ‘ 𝑎 )  ∈  𝑊 ) | 
						
							| 33 | 8 32 | sselid | ⊢ ( 𝑎  ∈  dom  𝑆  →  ( 𝑆 ‘ 𝑎 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 34 |  | lencl | ⊢ ( ( 𝑆 ‘ 𝑎 )  ∈  Word  ( 𝐼  ×  2o )  →  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0 ) | 
						
							| 35 | 33 34 | syl | ⊢ ( 𝑎  ∈  dom  𝑆  →  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0 ) | 
						
							| 36 |  | nn0nlt0 | ⊢ ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0  →  ¬  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0 ) | 
						
							| 37 | 35 36 | syl | ⊢ ( 𝑎  ∈  dom  𝑆  →  ¬  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0 ) | 
						
							| 38 | 37 | pm2.21d | ⊢ ( 𝑎  ∈  dom  𝑆  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 39 | 38 | adantr | ⊢ ( ( 𝑎  ∈  dom  𝑆  ∧  𝑏  ∈  dom  𝑆 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 40 | 39 | rgen2 | ⊢ ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  0  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) | 
						
							| 41 |  | simpl1 | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 42 |  | simpl3l | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖 ) | 
						
							| 43 |  | breq2 | ⊢ ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖 ) ) | 
						
							| 44 | 43 | imbi1d | ⊢ ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 45 | 44 | 2ralbidv | ⊢ ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 46 | 42 45 | syl | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 47 | 41 46 | mpbird | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 48 |  | simpl2l | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  𝑐  ∈  dom  𝑆 ) | 
						
							| 49 |  | simpl2r | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  𝑑  ∈  dom  𝑆 ) | 
						
							| 50 |  | simpl3r | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) | 
						
							| 51 |  | simpr | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  →  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) | 
						
							| 52 | 1 2 3 4 5 6 47 48 49 50 51 | efgredlem | ⊢ ¬  ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) | 
						
							| 53 |  | iman | ⊢ ( ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  ↔  ¬  ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  ∧  ¬  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) | 
						
							| 54 | 52 53 | mpbir | ⊢ ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) ) )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) | 
						
							| 55 | 54 | 3expia | ⊢ ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 ) )  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ∧  ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 ) )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) | 
						
							| 56 | 55 | expd | ⊢ ( ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( 𝑐  ∈  dom  𝑆  ∧  𝑑  ∈  dom  𝑆 ) )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) ) | 
						
							| 57 | 56 | ralrimivva | ⊢ ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  →  ∀ 𝑐  ∈  dom  𝑆 ∀ 𝑑  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) ) | 
						
							| 58 |  | 2fveq3 | ⊢ ( 𝑐  =  𝑎  →  ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) ) ) | 
						
							| 59 | 58 | eqeq1d | ⊢ ( 𝑐  =  𝑎  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 ) ) | 
						
							| 60 |  | fveqeq2 | ⊢ ( 𝑐  =  𝑎  →  ( ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 )  ↔  ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑑 ) ) ) | 
						
							| 61 |  | fveq1 | ⊢ ( 𝑐  =  𝑎  →  ( 𝑐 ‘ 0 )  =  ( 𝑎 ‘ 0 ) ) | 
						
							| 62 | 61 | eqeq1d | ⊢ ( 𝑐  =  𝑎  →  ( ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 )  ↔  ( 𝑎 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) | 
						
							| 63 | 60 62 | imbi12d | ⊢ ( 𝑐  =  𝑎  →  ( ( ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  ↔  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) ) | 
						
							| 64 | 59 63 | imbi12d | ⊢ ( 𝑐  =  𝑎  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) ) ) ) | 
						
							| 65 |  | fveq2 | ⊢ ( 𝑑  =  𝑏  →  ( 𝑆 ‘ 𝑑 )  =  ( 𝑆 ‘ 𝑏 ) ) | 
						
							| 66 | 65 | eqeq2d | ⊢ ( 𝑑  =  𝑏  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑑 )  ↔  ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 ) ) ) | 
						
							| 67 |  | fveq1 | ⊢ ( 𝑑  =  𝑏  →  ( 𝑑 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) | 
						
							| 68 | 67 | eqeq2d | ⊢ ( 𝑑  =  𝑏  →  ( ( 𝑎 ‘ 0 )  =  ( 𝑑 ‘ 0 )  ↔  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) | 
						
							| 69 | 66 68 | imbi12d | ⊢ ( 𝑑  =  𝑏  →  ( ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑑 ‘ 0 ) )  ↔  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 70 | 69 | imbi2d | ⊢ ( 𝑑  =  𝑏  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 71 | 64 70 | cbvral2vw | ⊢ ( ∀ 𝑐  ∈  dom  𝑆 ∀ 𝑑  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑐 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑐 )  =  ( 𝑆 ‘ 𝑑 )  →  ( 𝑐 ‘ 0 )  =  ( 𝑑 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 72 | 57 71 | sylib | ⊢ ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  →  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 73 | 72 | ancli | ⊢ ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 74 | 35 | adantr | ⊢ ( ( 𝑎  ∈  dom  𝑆  ∧  𝑏  ∈  dom  𝑆 )  →  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0 ) | 
						
							| 75 |  | nn0leltp1 | ⊢ ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0  ∧  𝑖  ∈  ℕ0 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ≤  𝑖  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 ) ) ) | 
						
							| 76 |  | nn0re | ⊢ ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0  →  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℝ ) | 
						
							| 77 |  | nn0re | ⊢ ( 𝑖  ∈  ℕ0  →  𝑖  ∈  ℝ ) | 
						
							| 78 |  | leloe | ⊢ ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℝ  ∧  𝑖  ∈  ℝ )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ≤  𝑖  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 ) ) ) | 
						
							| 79 | 76 77 78 | syl2an | ⊢ ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0  ∧  𝑖  ∈  ℕ0 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ≤  𝑖  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 ) ) ) | 
						
							| 80 | 75 79 | bitr3d | ⊢ ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0  ∧  𝑖  ∈  ℕ0 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 ) ) ) | 
						
							| 81 | 80 | ancoms | ⊢ ( ( 𝑖  ∈  ℕ0  ∧  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  ∈  ℕ0 )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 ) ) ) | 
						
							| 82 | 74 81 | sylan2 | ⊢ ( ( 𝑖  ∈  ℕ0  ∧  ( 𝑎  ∈  dom  𝑆  ∧  𝑏  ∈  dom  𝑆 ) )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 ) ) ) | 
						
							| 83 | 82 | imbi1d | ⊢ ( ( 𝑖  ∈  ℕ0  ∧  ( 𝑎  ∈  dom  𝑆  ∧  𝑏  ∈  dom  𝑆 ) )  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 84 |  | jaob | ⊢ ( ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  ∨  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 85 | 83 84 | bitrdi | ⊢ ( ( 𝑖  ∈  ℕ0  ∧  ( 𝑎  ∈  dom  𝑆  ∧  𝑏  ∈  dom  𝑆 ) )  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) ) | 
						
							| 86 | 85 | 2ralbidva | ⊢ ( 𝑖  ∈  ℕ0  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) ) | 
						
							| 87 |  | r19.26-2 | ⊢ ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) )  ↔  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 88 | 86 87 | bitrdi | ⊢ ( 𝑖  ∈  ℕ0  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ∧  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) ) | 
						
							| 89 | 73 88 | imbitrrid | ⊢ ( 𝑖  ∈  ℕ0  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  𝑖  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  →  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( 𝑖  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 90 | 22 25 28 31 40 89 | nn0ind | ⊢ ( ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  ∈  ℕ0  →  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 91 | 19 90 | syl | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 92 | 17 | nn0red | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  ∈  ℝ ) | 
						
							| 93 | 92 | ltp1d | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 ) ) | 
						
							| 94 |  | 2fveq3 | ⊢ ( 𝑎  =  𝐴  →  ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  =  ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) ) ) | 
						
							| 95 | 94 | breq1d | ⊢ ( 𝑎  =  𝐴  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  ↔  ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 ) ) ) | 
						
							| 96 |  | fveqeq2 | ⊢ ( 𝑎  =  𝐴  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  ↔  ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝑏 ) ) ) | 
						
							| 97 |  | fveq1 | ⊢ ( 𝑎  =  𝐴  →  ( 𝑎 ‘ 0 )  =  ( 𝐴 ‘ 0 ) ) | 
						
							| 98 | 97 | eqeq1d | ⊢ ( 𝑎  =  𝐴  →  ( ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 )  ↔  ( 𝐴 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) | 
						
							| 99 | 96 98 | imbi12d | ⊢ ( 𝑎  =  𝐴  →  ( ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) )  ↔  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝐴 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) | 
						
							| 100 | 95 99 | imbi12d | ⊢ ( 𝑎  =  𝐴  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝐴 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) ) ) ) | 
						
							| 101 |  | fveq2 | ⊢ ( 𝑏  =  𝐵  →  ( 𝑆 ‘ 𝑏 )  =  ( 𝑆 ‘ 𝐵 ) ) | 
						
							| 102 | 101 | eqeq2d | ⊢ ( 𝑏  =  𝐵  →  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝑏 )  ↔  ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝐵 ) ) ) | 
						
							| 103 |  | fveq1 | ⊢ ( 𝑏  =  𝐵  →  ( 𝑏 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) | 
						
							| 104 | 103 | eqeq2d | ⊢ ( 𝑏  =  𝐵  →  ( ( 𝐴 ‘ 0 )  =  ( 𝑏 ‘ 0 )  ↔  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) ) | 
						
							| 105 | 102 104 | imbi12d | ⊢ ( 𝑏  =  𝐵  →  ( ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝐴 ‘ 0 )  =  ( 𝑏 ‘ 0 ) )  ↔  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝐵 )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) ) ) | 
						
							| 106 | 105 | imbi2d | ⊢ ( 𝑏  =  𝐵  →  ( ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝐴 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  ↔  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝐵 )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) ) ) ) | 
						
							| 107 | 100 106 | rspc2v | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ∀ 𝑎  ∈  dom  𝑆 ∀ 𝑏  ∈  dom  𝑆 ( ( ♯ ‘ ( 𝑆 ‘ 𝑎 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝑎 )  =  ( 𝑆 ‘ 𝑏 )  →  ( 𝑎 ‘ 0 )  =  ( 𝑏 ‘ 0 ) ) )  →  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  <  ( ( ♯ ‘ ( 𝑆 ‘ 𝐴 ) )  +  1 )  →  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝐵 )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) ) ) ) | 
						
							| 108 | 91 93 107 | mp2d | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆 )  →  ( ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝐵 )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) ) | 
						
							| 109 | 108 | 3impia | ⊢ ( ( 𝐴  ∈  dom  𝑆  ∧  𝐵  ∈  dom  𝑆  ∧  ( 𝑆 ‘ 𝐴 )  =  ( 𝑆 ‘ 𝐵 ) )  →  ( 𝐴 ‘ 0 )  =  ( 𝐵 ‘ 0 ) ) |