| 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 |  | efgcpbllem.1 | ⊢ 𝐿  =  { 〈 𝑖 ,  𝑗 〉  ∣  ( { 𝑖 ,  𝑗 }  ⊆  𝑊  ∧  ( ( 𝐴  ++  𝑖 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑗 )  ++  𝐵 ) ) } | 
						
							| 8 | 1 2 3 4 | efgval2 | ⊢  ∼   =  ∩  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) } | 
						
							| 9 | 7 | relopabiv | ⊢ Rel  𝐿 | 
						
							| 10 | 9 | a1i | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  Rel  𝐿 ) | 
						
							| 11 | 1 2 3 4 5 6 7 | efgcpbllema | ⊢ ( 𝑓 𝐿 𝑔  ↔  ( 𝑓  ∈  𝑊  ∧  𝑔  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑔 )  ++  𝐵 ) ) ) | 
						
							| 12 | 11 | simp2bi | ⊢ ( 𝑓 𝐿 𝑔  →  𝑔  ∈  𝑊 ) | 
						
							| 13 | 12 | adantl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓 𝐿 𝑔 )  →  𝑔  ∈  𝑊 ) | 
						
							| 14 | 11 | simp1bi | ⊢ ( 𝑓 𝐿 𝑔  →  𝑓  ∈  𝑊 ) | 
						
							| 15 | 14 | adantl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓 𝐿 𝑔 )  →  𝑓  ∈  𝑊 ) | 
						
							| 16 | 1 2 | efger | ⊢  ∼   Er  𝑊 | 
						
							| 17 | 16 | a1i | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓 𝐿 𝑔 )  →   ∼   Er  𝑊 ) | 
						
							| 18 | 11 | simp3bi | ⊢ ( 𝑓 𝐿 𝑔  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑔 )  ++  𝐵 ) ) | 
						
							| 19 | 18 | adantl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓 𝐿 𝑔 )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑔 )  ++  𝐵 ) ) | 
						
							| 20 | 17 19 | ersym | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓 𝐿 𝑔 )  →  ( ( 𝐴  ++  𝑔 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) | 
						
							| 21 | 1 2 3 4 5 6 7 | efgcpbllema | ⊢ ( 𝑔 𝐿 𝑓  ↔  ( 𝑔  ∈  𝑊  ∧  𝑓  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑔 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 22 | 13 15 20 21 | syl3anbrc | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓 𝐿 𝑔 )  →  𝑔 𝐿 𝑓 ) | 
						
							| 23 | 14 | ad2antrl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →  𝑓  ∈  𝑊 ) | 
						
							| 24 | 1 2 3 4 5 6 7 | efgcpbllema | ⊢ ( 𝑔 𝐿 ℎ  ↔  ( 𝑔  ∈  𝑊  ∧  ℎ  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑔 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ℎ )  ++  𝐵 ) ) ) | 
						
							| 25 | 24 | simp2bi | ⊢ ( 𝑔 𝐿 ℎ  →  ℎ  ∈  𝑊 ) | 
						
							| 26 | 25 | ad2antll | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →  ℎ  ∈  𝑊 ) | 
						
							| 27 | 16 | a1i | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →   ∼   Er  𝑊 ) | 
						
							| 28 | 18 | ad2antrl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑔 )  ++  𝐵 ) ) | 
						
							| 29 | 24 | simp3bi | ⊢ ( 𝑔 𝐿 ℎ  →  ( ( 𝐴  ++  𝑔 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ℎ )  ++  𝐵 ) ) | 
						
							| 30 | 29 | ad2antll | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →  ( ( 𝐴  ++  𝑔 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ℎ )  ++  𝐵 ) ) | 
						
							| 31 | 27 28 30 | ertrd | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ℎ )  ++  𝐵 ) ) | 
						
							| 32 | 1 2 3 4 5 6 7 | efgcpbllema | ⊢ ( 𝑓 𝐿 ℎ  ↔  ( 𝑓  ∈  𝑊  ∧  ℎ  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ℎ )  ++  𝐵 ) ) ) | 
						
							| 33 | 23 26 31 32 | syl3anbrc | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  ( 𝑓 𝐿 𝑔  ∧  𝑔 𝐿 ℎ ) )  →  𝑓 𝐿 ℎ ) | 
						
							| 34 | 16 | a1i | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →   ∼   Er  𝑊 ) | 
						
							| 35 |  | fviss | ⊢ (  I  ‘ Word  ( 𝐼  ×  2o ) )  ⊆  Word  ( 𝐼  ×  2o ) | 
						
							| 36 | 1 35 | eqsstri | ⊢ 𝑊  ⊆  Word  ( 𝐼  ×  2o ) | 
						
							| 37 |  | simpll | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝐴  ∈  𝑊 ) | 
						
							| 38 | 36 37 | sselid | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝐴  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 39 |  | simpr | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝑓  ∈  𝑊 ) | 
						
							| 40 | 36 39 | sselid | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝑓  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 41 |  | ccatcl | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  𝑓  ∈  Word  ( 𝐼  ×  2o ) )  →  ( 𝐴  ++  𝑓 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 42 | 38 40 41 | syl2anc | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( 𝐴  ++  𝑓 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 43 |  | simplr | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝐵  ∈  𝑊 ) | 
						
							| 44 | 36 43 | sselid | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝐵  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 45 |  | ccatcl | ⊢ ( ( ( 𝐴  ++  𝑓 )  ∈  Word  ( 𝐼  ×  2o )  ∧  𝐵  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 46 | 42 44 45 | syl2anc | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 47 | 1 | efgrcl | ⊢ ( 𝐴  ∈  𝑊  →  ( 𝐼  ∈  V  ∧  𝑊  =  Word  ( 𝐼  ×  2o ) ) ) | 
						
							| 48 | 47 | simprd | ⊢ ( 𝐴  ∈  𝑊  →  𝑊  =  Word  ( 𝐼  ×  2o ) ) | 
						
							| 49 | 48 | ad2antrr | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  𝑊  =  Word  ( 𝐼  ×  2o ) ) | 
						
							| 50 | 46 49 | eleqtrrd | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  𝑊 ) | 
						
							| 51 | 34 50 | erref | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) | 
						
							| 52 | 51 | ex | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  ( 𝑓  ∈  𝑊  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 53 | 52 | pm4.71d | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  ( 𝑓  ∈  𝑊  ↔  ( 𝑓  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) ) | 
						
							| 54 | 1 2 3 4 5 6 7 | efgcpbllema | ⊢ ( 𝑓 𝐿 𝑓  ↔  ( 𝑓  ∈  𝑊  ∧  𝑓  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 55 |  | df-3an | ⊢ ( ( 𝑓  ∈  𝑊  ∧  𝑓  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  ↔  ( ( 𝑓  ∈  𝑊  ∧  𝑓  ∈  𝑊 )  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 56 |  | anidm | ⊢ ( ( 𝑓  ∈  𝑊  ∧  𝑓  ∈  𝑊 )  ↔  𝑓  ∈  𝑊 ) | 
						
							| 57 | 56 | anbi1i | ⊢ ( ( ( 𝑓  ∈  𝑊  ∧  𝑓  ∈  𝑊 )  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  ↔  ( 𝑓  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 58 | 54 55 57 | 3bitri | ⊢ ( 𝑓 𝐿 𝑓  ↔  ( 𝑓  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 59 | 53 58 | bitr4di | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  ( 𝑓  ∈  𝑊  ↔  𝑓 𝐿 𝑓 ) ) | 
						
							| 60 | 10 22 33 59 | iserd | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  𝐿  Er  𝑊 ) | 
						
							| 61 | 1 2 3 4 | efgtf | ⊢ ( 𝑓  ∈  𝑊  →  ( ( 𝑇 ‘ 𝑓 )  =  ( 𝑎  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ,  𝑏  ∈  ( 𝐼  ×  2o )  ↦  ( 𝑓  splice  〈 𝑎 ,  𝑎 ,  〈“ 𝑏 ( 𝑀 ‘ 𝑏 ) ”〉 〉 ) )  ∧  ( 𝑇 ‘ 𝑓 ) : ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊 ) ) | 
						
							| 62 | 61 | simprd | ⊢ ( 𝑓  ∈  𝑊  →  ( 𝑇 ‘ 𝑓 ) : ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊 ) | 
						
							| 63 | 62 | adantl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( 𝑇 ‘ 𝑓 ) : ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊 ) | 
						
							| 64 |  | ffn | ⊢ ( ( 𝑇 ‘ 𝑓 ) : ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊  →  ( 𝑇 ‘ 𝑓 )  Fn  ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) ) ) | 
						
							| 65 |  | ovelrn | ⊢ ( ( 𝑇 ‘ 𝑓 )  Fn  ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) )  →  ( 𝑎  ∈  ran  ( 𝑇 ‘ 𝑓 )  ↔  ∃ 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ∃ 𝑢  ∈  ( 𝐼  ×  2o ) 𝑎  =  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) ) ) | 
						
							| 66 | 63 64 65 | 3syl | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( 𝑎  ∈  ran  ( 𝑇 ‘ 𝑓 )  ↔  ∃ 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ∃ 𝑢  ∈  ( 𝐼  ×  2o ) 𝑎  =  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) ) ) | 
						
							| 67 |  | simplr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑓  ∈  𝑊 ) | 
						
							| 68 | 62 | ad2antlr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑇 ‘ 𝑓 ) : ( ( 0 ... ( ♯ ‘ 𝑓 ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊 ) | 
						
							| 69 |  | simprl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 70 |  | simprr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑢  ∈  ( 𝐼  ×  2o ) ) | 
						
							| 71 | 68 69 70 | fovcdmd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  ∈  𝑊 ) | 
						
							| 72 | 50 | adantr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  𝑊 ) | 
						
							| 73 | 37 | adantr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝐴  ∈  𝑊 ) | 
						
							| 74 | 36 73 | sselid | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝐴  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 75 | 40 | adantr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑓  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 76 |  | pfxcl | ⊢ ( 𝑓  ∈  Word  ( 𝐼  ×  2o )  →  ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 77 | 75 76 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 78 |  | ccatcl | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o ) )  →  ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 79 | 74 77 78 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 80 | 3 | efgmf | ⊢ 𝑀 : ( 𝐼  ×  2o ) ⟶ ( 𝐼  ×  2o ) | 
						
							| 81 | 80 | ffvelcdmi | ⊢ ( 𝑢  ∈  ( 𝐼  ×  2o )  →  ( 𝑀 ‘ 𝑢 )  ∈  ( 𝐼  ×  2o ) ) | 
						
							| 82 | 81 | ad2antll | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑀 ‘ 𝑢 )  ∈  ( 𝐼  ×  2o ) ) | 
						
							| 83 | 70 82 | s2cld | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 84 |  | ccatcl | ⊢ ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ∈  Word  ( 𝐼  ×  2o )  ∧  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 85 | 79 83 84 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 86 |  | swrdcl | ⊢ ( 𝑓  ∈  Word  ( 𝐼  ×  2o )  →  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 87 | 75 86 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 88 | 44 | adantr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝐵  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 89 |  | ccatass | ⊢ ( ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o )  ∧  𝐵  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  ++  𝐵 )  =  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 90 | 85 87 88 89 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  ++  𝐵 )  =  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 91 |  | ccatcl | ⊢ ( ( ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o )  ∧  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 92 | 77 83 91 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 93 |  | ccatass | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝐴  ++  ( ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) ) | 
						
							| 94 | 74 92 87 93 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝐴  ++  ( ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) ) | 
						
							| 95 |  | ccatass | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o )  ∧  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  =  ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 ) ) ) | 
						
							| 96 | 74 77 83 95 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  =  ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 ) ) ) | 
						
							| 97 | 96 | oveq1d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) | 
						
							| 98 | 1 2 3 4 | efgtval | ⊢ ( ( 𝑓  ∈  𝑊  ∧  𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) )  →  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  =  ( 𝑓  splice  〈 𝑐 ,  𝑐 ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 ) ) | 
						
							| 99 | 67 69 70 98 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  =  ( 𝑓  splice  〈 𝑐 ,  𝑐 ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 ) ) | 
						
							| 100 |  | splval | ⊢ ( ( 𝑓  ∈  𝑊  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉  ∈  Word  ( 𝐼  ×  2o ) ) )  →  ( 𝑓  splice  〈 𝑐 ,  𝑐 ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 )  =  ( ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) | 
						
							| 101 | 67 69 69 83 100 | syl13anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑓  splice  〈 𝑐 ,  𝑐 ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 )  =  ( ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) | 
						
							| 102 | 99 101 | eqtrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  =  ( ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) | 
						
							| 103 | 102 | oveq2d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  =  ( 𝐴  ++  ( ( ( 𝑓  prefix  𝑐 )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) ) | 
						
							| 104 | 94 97 103 | 3eqtr4rd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  =  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) | 
						
							| 105 | 104 | oveq1d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 )  =  ( ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  ++  𝐵 ) ) | 
						
							| 106 |  | lencl | ⊢ ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  →  ( ♯ ‘ 𝐴 )  ∈  ℕ0 ) | 
						
							| 107 | 74 106 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝐴 )  ∈  ℕ0 ) | 
						
							| 108 |  | nn0uz | ⊢ ℕ0  =  ( ℤ≥ ‘ 0 ) | 
						
							| 109 | 107 108 | eleqtrdi | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝐴 )  ∈  ( ℤ≥ ‘ 0 ) ) | 
						
							| 110 |  | elfznn0 | ⊢ ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  →  𝑐  ∈  ℕ0 ) | 
						
							| 111 | 110 | ad2antrl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑐  ∈  ℕ0 ) | 
						
							| 112 |  | uzaddcl | ⊢ ( ( ( ♯ ‘ 𝐴 )  ∈  ( ℤ≥ ‘ 0 )  ∧  𝑐  ∈  ℕ0 )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( ℤ≥ ‘ 0 ) ) | 
						
							| 113 | 109 111 112 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( ℤ≥ ‘ 0 ) ) | 
						
							| 114 | 42 | adantr | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝐴  ++  𝑓 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 115 |  | ccatlen | ⊢ ( ( ( 𝐴  ++  𝑓 )  ∈  Word  ( 𝐼  ×  2o )  ∧  𝐵  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  =  ( ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  +  ( ♯ ‘ 𝐵 ) ) ) | 
						
							| 116 | 114 88 115 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  =  ( ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  +  ( ♯ ‘ 𝐵 ) ) ) | 
						
							| 117 |  | ccatlen | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  𝑓  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  =  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 118 | 74 75 117 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  =  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 119 |  | elfzuz3 | ⊢ ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  →  ( ♯ ‘ 𝑓 )  ∈  ( ℤ≥ ‘ 𝑐 ) ) | 
						
							| 120 | 119 | ad2antrl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝑓 )  ∈  ( ℤ≥ ‘ 𝑐 ) ) | 
						
							| 121 | 107 | nn0zd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝐴 )  ∈  ℤ ) | 
						
							| 122 |  | eluzadd | ⊢ ( ( ( ♯ ‘ 𝑓 )  ∈  ( ℤ≥ ‘ 𝑐 )  ∧  ( ♯ ‘ 𝐴 )  ∈  ℤ )  →  ( ( ♯ ‘ 𝑓 )  +  ( ♯ ‘ 𝐴 ) )  ∈  ( ℤ≥ ‘ ( 𝑐  +  ( ♯ ‘ 𝐴 ) ) ) ) | 
						
							| 123 | 120 121 122 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝑓 )  +  ( ♯ ‘ 𝐴 ) )  ∈  ( ℤ≥ ‘ ( 𝑐  +  ( ♯ ‘ 𝐴 ) ) ) ) | 
						
							| 124 |  | lencl | ⊢ ( 𝑓  ∈  Word  ( 𝐼  ×  2o )  →  ( ♯ ‘ 𝑓 )  ∈  ℕ0 ) | 
						
							| 125 | 75 124 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝑓 )  ∈  ℕ0 ) | 
						
							| 126 | 125 | nn0cnd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝑓 )  ∈  ℂ ) | 
						
							| 127 | 107 | nn0cnd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝐴 )  ∈  ℂ ) | 
						
							| 128 | 126 127 | addcomd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝑓 )  +  ( ♯ ‘ 𝐴 ) )  =  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 129 | 111 | nn0cnd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑐  ∈  ℂ ) | 
						
							| 130 | 129 127 | addcomd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑐  +  ( ♯ ‘ 𝐴 ) )  =  ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) | 
						
							| 131 | 130 | fveq2d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ℤ≥ ‘ ( 𝑐  +  ( ♯ ‘ 𝐴 ) ) )  =  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) | 
						
							| 132 | 123 128 131 | 3eltr3d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ 𝑓 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) | 
						
							| 133 | 118 132 | eqeltrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) | 
						
							| 134 |  | lencl | ⊢ ( 𝐵  ∈  Word  ( 𝐼  ×  2o )  →  ( ♯ ‘ 𝐵 )  ∈  ℕ0 ) | 
						
							| 135 | 88 134 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝐵 )  ∈  ℕ0 ) | 
						
							| 136 |  | uzaddcl | ⊢ ( ( ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) )  ∧  ( ♯ ‘ 𝐵 )  ∈  ℕ0 )  →  ( ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  +  ( ♯ ‘ 𝐵 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) | 
						
							| 137 | 133 135 136 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ ( 𝐴  ++  𝑓 ) )  +  ( ♯ ‘ 𝐵 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) | 
						
							| 138 | 116 137 | eqeltrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) | 
						
							| 139 |  | elfzuzb | ⊢ ( ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ↔  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( ℤ≥ ‘ 0 )  ∧  ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  ∈  ( ℤ≥ ‘ ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) ) ) | 
						
							| 140 | 113 138 139 | sylanbrc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) ) | 
						
							| 141 | 1 2 3 4 | efgtval | ⊢ ( ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  𝑊  ∧  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) )  →  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) 𝑢 )  =  ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  splice  〈 ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ,  ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 ) ) | 
						
							| 142 | 72 140 70 141 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) 𝑢 )  =  ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  splice  〈 ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ,  ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 ) ) | 
						
							| 143 |  | wrd0 | ⊢ ∅  ∈  Word  ( 𝐼  ×  2o ) | 
						
							| 144 | 143 | a1i | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ∅  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 145 |  | ccatcl | ⊢ ( ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o )  ∧  𝐵  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 146 | 87 88 145 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 )  ∈  Word  ( 𝐼  ×  2o ) ) | 
						
							| 147 |  | ccatrid | ⊢ ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ∈  Word  ( 𝐼  ×  2o )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ∅ )  =  ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) ) ) | 
						
							| 148 | 79 147 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ∅ )  =  ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) ) ) | 
						
							| 149 | 148 | oveq1d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ∅ )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) )  =  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 150 |  | ccatass | ⊢ ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o )  ∧  𝐵  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  ++  𝐵 )  =  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 151 | 79 87 88 150 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  ++  𝐵 )  =  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 152 |  | ccatass | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) ) | 
						
							| 153 | 74 77 87 152 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) ) ) | 
						
							| 154 | 125 108 | eleqtrdi | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝑓 )  ∈  ( ℤ≥ ‘ 0 ) ) | 
						
							| 155 |  | eluzfz2 | ⊢ ( ( ♯ ‘ 𝑓 )  ∈  ( ℤ≥ ‘ 0 )  →  ( ♯ ‘ 𝑓 )  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 156 | 154 155 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ 𝑓 )  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 157 |  | ccatpfx | ⊢ ( ( 𝑓  ∈  Word  ( 𝐼  ×  2o )  ∧  𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  ( ♯ ‘ 𝑓 )  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) )  →  ( ( 𝑓  prefix  𝑐 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝑓  prefix  ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 158 | 75 69 156 157 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝑓  prefix  𝑐 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝑓  prefix  ( ♯ ‘ 𝑓 ) ) ) | 
						
							| 159 |  | pfxid | ⊢ ( 𝑓  ∈  Word  ( 𝐼  ×  2o )  →  ( 𝑓  prefix  ( ♯ ‘ 𝑓 ) )  =  𝑓 ) | 
						
							| 160 | 75 159 | syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑓  prefix  ( ♯ ‘ 𝑓 ) )  =  𝑓 ) | 
						
							| 161 | 158 160 | eqtrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝑓  prefix  𝑐 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  𝑓 ) | 
						
							| 162 | 161 | oveq2d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝐴  ++  ( ( 𝑓  prefix  𝑐 )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) ) )  =  ( 𝐴  ++  𝑓 ) ) | 
						
							| 163 | 153 162 | eqtrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  =  ( 𝐴  ++  𝑓 ) ) | 
						
							| 164 | 163 | oveq1d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 ) )  ++  𝐵 )  =  ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) | 
						
							| 165 | 149 151 164 | 3eqtr2rd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  =  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  ∅ )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 166 |  | ccatlen | ⊢ ( ( 𝐴  ∈  Word  ( 𝐼  ×  2o )  ∧  ( 𝑓  prefix  𝑐 )  ∈  Word  ( 𝐼  ×  2o ) )  →  ( ♯ ‘ ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) ) )  =  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ ( 𝑓  prefix  𝑐 ) ) ) ) | 
						
							| 167 | 74 77 166 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) ) )  =  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ ( 𝑓  prefix  𝑐 ) ) ) ) | 
						
							| 168 |  | pfxlen | ⊢ ( ( 𝑓  ∈  Word  ( 𝐼  ×  2o )  ∧  𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) )  →  ( ♯ ‘ ( 𝑓  prefix  𝑐 ) )  =  𝑐 ) | 
						
							| 169 | 75 69 168 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ♯ ‘ ( 𝑓  prefix  𝑐 ) )  =  𝑐 ) | 
						
							| 170 | 169 | oveq2d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  ( ♯ ‘ ( 𝑓  prefix  𝑐 ) ) )  =  ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) | 
						
							| 171 | 167 170 | eqtr2d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  =  ( ♯ ‘ ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) ) ) ) | 
						
							| 172 |  | hash0 | ⊢ ( ♯ ‘ ∅ )  =  0 | 
						
							| 173 | 172 | oveq2i | ⊢ ( ( ( ♯ ‘ 𝐴 )  +  𝑐 )  +  ( ♯ ‘ ∅ ) )  =  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 )  +  0 ) | 
						
							| 174 | 107 111 | nn0addcld | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ℕ0 ) | 
						
							| 175 | 174 | nn0cnd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ℂ ) | 
						
							| 176 | 175 | addridd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 )  +  0 )  =  ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ) | 
						
							| 177 | 173 176 | eqtr2id | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  =  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 )  +  ( ♯ ‘ ∅ ) ) ) | 
						
							| 178 | 79 144 146 83 165 171 177 | splval2 | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  splice  〈 ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ,  ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ,  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 〉 )  =  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 179 | 142 178 | eqtrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) 𝑢 )  =  ( ( ( 𝐴  ++  ( 𝑓  prefix  𝑐 ) )  ++  〈“ 𝑢 ( 𝑀 ‘ 𝑢 ) ”〉 )  ++  ( ( 𝑓  substr  〈 𝑐 ,  ( ♯ ‘ 𝑓 ) 〉 )  ++  𝐵 ) ) ) | 
						
							| 180 | 90 105 179 | 3eqtr4d | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 )  =  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) 𝑢 ) ) | 
						
							| 181 | 1 2 3 4 | efgtf | ⊢ ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  𝑊  →  ( ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  =  ( 𝑎  ∈  ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) ,  𝑏  ∈  ( 𝐼  ×  2o )  ↦  ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  splice  〈 𝑎 ,  𝑎 ,  〈“ 𝑏 ( 𝑀 ‘ 𝑏 ) ”〉 〉 ) )  ∧  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) : ( ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊 ) ) | 
						
							| 182 | 181 | simprd | ⊢ ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  𝑊  →  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) : ( ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊 ) | 
						
							| 183 |  | ffn | ⊢ ( ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) : ( ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ×  ( 𝐼  ×  2o ) ) ⟶ 𝑊  →  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  Fn  ( ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ×  ( 𝐼  ×  2o ) ) ) | 
						
							| 184 | 72 182 183 | 3syl | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  Fn  ( ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ×  ( 𝐼  ×  2o ) ) ) | 
						
							| 185 |  | fnovrn | ⊢ ( ( ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) )  Fn  ( ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ×  ( 𝐼  ×  2o ) )  ∧  ( ( ♯ ‘ 𝐴 )  +  𝑐 )  ∈  ( 0 ... ( ♯ ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) )  →  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) 𝑢 )  ∈  ran  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 186 | 184 140 70 185 | syl3anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( ( ♯ ‘ 𝐴 )  +  𝑐 ) ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) 𝑢 )  ∈  ran  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 187 | 180 186 | eqeltrd | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 )  ∈  ran  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) ) | 
						
							| 188 | 1 2 3 4 | efgi2 | ⊢ ( ( ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∈  𝑊  ∧  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 )  ∈  ran  ( 𝑇 ‘ ( ( 𝐴  ++  𝑓 )  ++  𝐵 ) ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 ) ) | 
						
							| 189 | 72 187 188 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 ) ) | 
						
							| 190 | 1 2 3 4 5 6 7 | efgcpbllema | ⊢ ( 𝑓 𝐿 ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  ↔  ( 𝑓  ∈  𝑊  ∧  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  ∈  𝑊  ∧  ( ( 𝐴  ++  𝑓 )  ++  𝐵 )  ∼  ( ( 𝐴  ++  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) )  ++  𝐵 ) ) ) | 
						
							| 191 | 67 71 189 190 | syl3anbrc | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  𝑓 𝐿 ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) ) | 
						
							| 192 |  | vex | ⊢ 𝑎  ∈  V | 
						
							| 193 |  | vex | ⊢ 𝑓  ∈  V | 
						
							| 194 | 192 193 | elec | ⊢ ( 𝑎  ∈  [ 𝑓 ] 𝐿  ↔  𝑓 𝐿 𝑎 ) | 
						
							| 195 |  | breq2 | ⊢ ( 𝑎  =  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  →  ( 𝑓 𝐿 𝑎  ↔  𝑓 𝐿 ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) ) ) | 
						
							| 196 | 194 195 | bitrid | ⊢ ( 𝑎  =  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  →  ( 𝑎  ∈  [ 𝑓 ] 𝐿  ↔  𝑓 𝐿 ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 ) ) ) | 
						
							| 197 | 191 196 | syl5ibrcom | ⊢ ( ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  ∧  ( 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) )  ∧  𝑢  ∈  ( 𝐼  ×  2o ) ) )  →  ( 𝑎  =  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  →  𝑎  ∈  [ 𝑓 ] 𝐿 ) ) | 
						
							| 198 | 197 | rexlimdvva | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( ∃ 𝑐  ∈  ( 0 ... ( ♯ ‘ 𝑓 ) ) ∃ 𝑢  ∈  ( 𝐼  ×  2o ) 𝑎  =  ( 𝑐 ( 𝑇 ‘ 𝑓 ) 𝑢 )  →  𝑎  ∈  [ 𝑓 ] 𝐿 ) ) | 
						
							| 199 | 66 198 | sylbid | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ( 𝑎  ∈  ran  ( 𝑇 ‘ 𝑓 )  →  𝑎  ∈  [ 𝑓 ] 𝐿 ) ) | 
						
							| 200 | 199 | ssrdv | ⊢ ( ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  ∧  𝑓  ∈  𝑊 )  →  ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) | 
						
							| 201 | 200 | ralrimiva | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) | 
						
							| 202 | 1 | fvexi | ⊢ 𝑊  ∈  V | 
						
							| 203 |  | erex | ⊢ ( 𝐿  Er  𝑊  →  ( 𝑊  ∈  V  →  𝐿  ∈  V ) ) | 
						
							| 204 | 60 202 203 | mpisyl | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  𝐿  ∈  V ) | 
						
							| 205 |  | ereq1 | ⊢ ( 𝑟  =  𝐿  →  ( 𝑟  Er  𝑊  ↔  𝐿  Er  𝑊 ) ) | 
						
							| 206 |  | eceq2 | ⊢ ( 𝑟  =  𝐿  →  [ 𝑓 ] 𝑟  =  [ 𝑓 ] 𝐿 ) | 
						
							| 207 | 206 | sseq2d | ⊢ ( 𝑟  =  𝐿  →  ( ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟  ↔  ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) ) | 
						
							| 208 | 207 | ralbidv | ⊢ ( 𝑟  =  𝐿  →  ( ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟  ↔  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) ) | 
						
							| 209 | 205 208 | anbi12d | ⊢ ( 𝑟  =  𝐿  →  ( ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 )  ↔  ( 𝐿  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) ) ) | 
						
							| 210 | 209 | elabg | ⊢ ( 𝐿  ∈  V  →  ( 𝐿  ∈  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) }  ↔  ( 𝐿  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) ) ) | 
						
							| 211 | 204 210 | syl | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  ( 𝐿  ∈  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) }  ↔  ( 𝐿  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝐿 ) ) ) | 
						
							| 212 | 60 201 211 | mpbir2and | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  𝐿  ∈  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) } ) | 
						
							| 213 |  | intss1 | ⊢ ( 𝐿  ∈  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) }  →  ∩  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) }  ⊆  𝐿 ) | 
						
							| 214 | 212 213 | syl | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →  ∩  { 𝑟  ∣  ( 𝑟  Er  𝑊  ∧  ∀ 𝑓  ∈  𝑊 ran  ( 𝑇 ‘ 𝑓 )  ⊆  [ 𝑓 ] 𝑟 ) }  ⊆  𝐿 ) | 
						
							| 215 | 8 214 | eqsstrid | ⊢ ( ( 𝐴  ∈  𝑊  ∧  𝐵  ∈  𝑊 )  →   ∼   ⊆  𝐿 ) |