| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cycpmco2.c | ⊢ 𝑀  =  ( toCyc ‘ 𝐷 ) | 
						
							| 2 |  | cycpmco2.s | ⊢ 𝑆  =  ( SymGrp ‘ 𝐷 ) | 
						
							| 3 |  | cycpmco2.d | ⊢ ( 𝜑  →  𝐷  ∈  𝑉 ) | 
						
							| 4 |  | cycpmco2.w | ⊢ ( 𝜑  →  𝑊  ∈  dom  𝑀 ) | 
						
							| 5 |  | cycpmco2.i | ⊢ ( 𝜑  →  𝐼  ∈  ( 𝐷  ∖  ran  𝑊 ) ) | 
						
							| 6 |  | cycpmco2.j | ⊢ ( 𝜑  →  𝐽  ∈  ran  𝑊 ) | 
						
							| 7 |  | cycpmco2.e | ⊢ 𝐸  =  ( ( ◡ 𝑊 ‘ 𝐽 )  +  1 ) | 
						
							| 8 |  | cycpmco2.1 | ⊢ 𝑈  =  ( 𝑊  splice  〈 𝐸 ,  𝐸 ,  〈“ 𝐼 ”〉 〉 ) | 
						
							| 9 |  | ssrab2 | ⊢ { 𝑤  ∈  Word  𝐷  ∣  𝑤 : dom  𝑤 –1-1→ 𝐷 }  ⊆  Word  𝐷 | 
						
							| 10 |  | eqid | ⊢ ( Base ‘ 𝑆 )  =  ( Base ‘ 𝑆 ) | 
						
							| 11 | 1 2 10 | tocycf | ⊢ ( 𝐷  ∈  𝑉  →  𝑀 : { 𝑤  ∈  Word  𝐷  ∣  𝑤 : dom  𝑤 –1-1→ 𝐷 } ⟶ ( Base ‘ 𝑆 ) ) | 
						
							| 12 | 3 11 | syl | ⊢ ( 𝜑  →  𝑀 : { 𝑤  ∈  Word  𝐷  ∣  𝑤 : dom  𝑤 –1-1→ 𝐷 } ⟶ ( Base ‘ 𝑆 ) ) | 
						
							| 13 | 12 | fdmd | ⊢ ( 𝜑  →  dom  𝑀  =  { 𝑤  ∈  Word  𝐷  ∣  𝑤 : dom  𝑤 –1-1→ 𝐷 } ) | 
						
							| 14 | 4 13 | eleqtrd | ⊢ ( 𝜑  →  𝑊  ∈  { 𝑤  ∈  Word  𝐷  ∣  𝑤 : dom  𝑤 –1-1→ 𝐷 } ) | 
						
							| 15 | 9 14 | sselid | ⊢ ( 𝜑  →  𝑊  ∈  Word  𝐷 ) | 
						
							| 16 |  | pfxcl | ⊢ ( 𝑊  ∈  Word  𝐷  →  ( 𝑊  prefix  𝐸 )  ∈  Word  𝐷 ) | 
						
							| 17 | 15 16 | syl | ⊢ ( 𝜑  →  ( 𝑊  prefix  𝐸 )  ∈  Word  𝐷 ) | 
						
							| 18 | 5 | eldifad | ⊢ ( 𝜑  →  𝐼  ∈  𝐷 ) | 
						
							| 19 | 18 | s1cld | ⊢ ( 𝜑  →  〈“ 𝐼 ”〉  ∈  Word  𝐷 ) | 
						
							| 20 |  | ccatcl | ⊢ ( ( ( 𝑊  prefix  𝐸 )  ∈  Word  𝐷  ∧  〈“ 𝐼 ”〉  ∈  Word  𝐷 )  →  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ∈  Word  𝐷 ) | 
						
							| 21 | 17 19 20 | syl2anc | ⊢ ( 𝜑  →  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ∈  Word  𝐷 ) | 
						
							| 22 |  | swrdcl | ⊢ ( 𝑊  ∈  Word  𝐷  →  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∈  Word  𝐷 ) | 
						
							| 23 | 15 22 | syl | ⊢ ( 𝜑  →  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∈  Word  𝐷 ) | 
						
							| 24 |  | id | ⊢ ( 𝑤  =  𝑊  →  𝑤  =  𝑊 ) | 
						
							| 25 |  | dmeq | ⊢ ( 𝑤  =  𝑊  →  dom  𝑤  =  dom  𝑊 ) | 
						
							| 26 |  | eqidd | ⊢ ( 𝑤  =  𝑊  →  𝐷  =  𝐷 ) | 
						
							| 27 | 24 25 26 | f1eq123d | ⊢ ( 𝑤  =  𝑊  →  ( 𝑤 : dom  𝑤 –1-1→ 𝐷  ↔  𝑊 : dom  𝑊 –1-1→ 𝐷 ) ) | 
						
							| 28 | 27 | elrab | ⊢ ( 𝑊  ∈  { 𝑤  ∈  Word  𝐷  ∣  𝑤 : dom  𝑤 –1-1→ 𝐷 }  ↔  ( 𝑊  ∈  Word  𝐷  ∧  𝑊 : dom  𝑊 –1-1→ 𝐷 ) ) | 
						
							| 29 | 14 28 | sylib | ⊢ ( 𝜑  →  ( 𝑊  ∈  Word  𝐷  ∧  𝑊 : dom  𝑊 –1-1→ 𝐷 ) ) | 
						
							| 30 | 29 | simprd | ⊢ ( 𝜑  →  𝑊 : dom  𝑊 –1-1→ 𝐷 ) | 
						
							| 31 |  | f1cnv | ⊢ ( 𝑊 : dom  𝑊 –1-1→ 𝐷  →  ◡ 𝑊 : ran  𝑊 –1-1-onto→ dom  𝑊 ) | 
						
							| 32 |  | f1of | ⊢ ( ◡ 𝑊 : ran  𝑊 –1-1-onto→ dom  𝑊  →  ◡ 𝑊 : ran  𝑊 ⟶ dom  𝑊 ) | 
						
							| 33 | 30 31 32 | 3syl | ⊢ ( 𝜑  →  ◡ 𝑊 : ran  𝑊 ⟶ dom  𝑊 ) | 
						
							| 34 | 33 6 | ffvelcdmd | ⊢ ( 𝜑  →  ( ◡ 𝑊 ‘ 𝐽 )  ∈  dom  𝑊 ) | 
						
							| 35 |  | wrddm | ⊢ ( 𝑊  ∈  Word  𝐷  →  dom  𝑊  =  ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 36 | 15 35 | syl | ⊢ ( 𝜑  →  dom  𝑊  =  ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 37 | 34 36 | eleqtrd | ⊢ ( 𝜑  →  ( ◡ 𝑊 ‘ 𝐽 )  ∈  ( 0 ..^ ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 38 |  | fzofzp1 | ⊢ ( ( ◡ 𝑊 ‘ 𝐽 )  ∈  ( 0 ..^ ( ♯ ‘ 𝑊 ) )  →  ( ( ◡ 𝑊 ‘ 𝐽 )  +  1 )  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 39 | 37 38 | syl | ⊢ ( 𝜑  →  ( ( ◡ 𝑊 ‘ 𝐽 )  +  1 )  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 40 | 7 39 | eqeltrid | ⊢ ( 𝜑  →  𝐸  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 41 | 15 30 40 | pfxf1 | ⊢ ( 𝜑  →  ( 𝑊  prefix  𝐸 ) : dom  ( 𝑊  prefix  𝐸 ) –1-1→ 𝐷 ) | 
						
							| 42 | 18 | s1f1 | ⊢ ( 𝜑  →  〈“ 𝐼 ”〉 : dom  〈“ 𝐼 ”〉 –1-1→ 𝐷 ) | 
						
							| 43 |  | s1rn | ⊢ ( 𝐼  ∈  𝐷  →  ran  〈“ 𝐼 ”〉  =  { 𝐼 } ) | 
						
							| 44 | 18 43 | syl | ⊢ ( 𝜑  →  ran  〈“ 𝐼 ”〉  =  { 𝐼 } ) | 
						
							| 45 | 44 | ineq2d | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  〈“ 𝐼 ”〉 )  =  ( ran  ( 𝑊  prefix  𝐸 )  ∩  { 𝐼 } ) ) | 
						
							| 46 |  | pfxrn2 | ⊢ ( ( 𝑊  ∈  Word  𝐷  ∧  𝐸  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) )  →  ran  ( 𝑊  prefix  𝐸 )  ⊆  ran  𝑊 ) | 
						
							| 47 | 15 40 46 | syl2anc | ⊢ ( 𝜑  →  ran  ( 𝑊  prefix  𝐸 )  ⊆  ran  𝑊 ) | 
						
							| 48 | 47 | ssrind | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  { 𝐼 } )  ⊆  ( ran  𝑊  ∩  { 𝐼 } ) ) | 
						
							| 49 | 5 | eldifbd | ⊢ ( 𝜑  →  ¬  𝐼  ∈  ran  𝑊 ) | 
						
							| 50 |  | disjsn | ⊢ ( ( ran  𝑊  ∩  { 𝐼 } )  =  ∅  ↔  ¬  𝐼  ∈  ran  𝑊 ) | 
						
							| 51 | 49 50 | sylibr | ⊢ ( 𝜑  →  ( ran  𝑊  ∩  { 𝐼 } )  =  ∅ ) | 
						
							| 52 | 48 51 | sseqtrd | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  { 𝐼 } )  ⊆  ∅ ) | 
						
							| 53 |  | ss0 | ⊢ ( ( ran  ( 𝑊  prefix  𝐸 )  ∩  { 𝐼 } )  ⊆  ∅  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  { 𝐼 } )  =  ∅ ) | 
						
							| 54 | 52 53 | syl | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  { 𝐼 } )  =  ∅ ) | 
						
							| 55 | 45 54 | eqtrd | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  〈“ 𝐼 ”〉 )  =  ∅ ) | 
						
							| 56 | 3 17 19 41 42 55 | ccatf1 | ⊢ ( 𝜑  →  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 ) : dom  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 ) –1-1→ 𝐷 ) | 
						
							| 57 |  | lencl | ⊢ ( 𝑊  ∈  Word  𝐷  →  ( ♯ ‘ 𝑊 )  ∈  ℕ0 ) | 
						
							| 58 |  | nn0fz0 | ⊢ ( ( ♯ ‘ 𝑊 )  ∈  ℕ0  ↔  ( ♯ ‘ 𝑊 )  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 59 | 58 | biimpi | ⊢ ( ( ♯ ‘ 𝑊 )  ∈  ℕ0  →  ( ♯ ‘ 𝑊 )  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 60 | 15 57 59 | 3syl | ⊢ ( 𝜑  →  ( ♯ ‘ 𝑊 )  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 61 | 15 40 60 30 | swrdf1 | ⊢ ( 𝜑  →  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) : dom  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) –1-1→ 𝐷 ) | 
						
							| 62 |  | ccatrn | ⊢ ( ( ( 𝑊  prefix  𝐸 )  ∈  Word  𝐷  ∧  〈“ 𝐼 ”〉  ∈  Word  𝐷 )  →  ran  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  =  ( ran  ( 𝑊  prefix  𝐸 )  ∪  ran  〈“ 𝐼 ”〉 ) ) | 
						
							| 63 | 17 19 62 | syl2anc | ⊢ ( 𝜑  →  ran  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  =  ( ran  ( 𝑊  prefix  𝐸 )  ∪  ran  〈“ 𝐼 ”〉 ) ) | 
						
							| 64 | 63 | ineq1d | ⊢ ( 𝜑  →  ( ran  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ( ( ran  ( 𝑊  prefix  𝐸 )  ∪  ran  〈“ 𝐼 ”〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 65 |  | indir | ⊢ ( ( ran  ( 𝑊  prefix  𝐸 )  ∪  ran  〈“ 𝐼 ”〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ( ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  ∪  ( ran  〈“ 𝐼 ”〉  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 66 | 64 65 | eqtrdi | ⊢ ( 𝜑  →  ( ran  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ( ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  ∪  ( ran  〈“ 𝐼 ”〉  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) ) | 
						
							| 67 |  | fz0ssnn0 | ⊢ ( 0 ... ( ♯ ‘ 𝑊 ) )  ⊆  ℕ0 | 
						
							| 68 | 67 40 | sselid | ⊢ ( 𝜑  →  𝐸  ∈  ℕ0 ) | 
						
							| 69 |  | pfxval | ⊢ ( ( 𝑊  ∈  Word  𝐷  ∧  𝐸  ∈  ℕ0 )  →  ( 𝑊  prefix  𝐸 )  =  ( 𝑊  substr  〈 0 ,  𝐸 〉 ) ) | 
						
							| 70 | 15 68 69 | syl2anc | ⊢ ( 𝜑  →  ( 𝑊  prefix  𝐸 )  =  ( 𝑊  substr  〈 0 ,  𝐸 〉 ) ) | 
						
							| 71 | 70 | rneqd | ⊢ ( 𝜑  →  ran  ( 𝑊  prefix  𝐸 )  =  ran  ( 𝑊  substr  〈 0 ,  𝐸 〉 ) ) | 
						
							| 72 | 71 | ineq1d | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ( ran  ( 𝑊  substr  〈 0 ,  𝐸 〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 73 |  | 0elfz | ⊢ ( 𝐸  ∈  ℕ0  →  0  ∈  ( 0 ... 𝐸 ) ) | 
						
							| 74 | 68 73 | syl | ⊢ ( 𝜑  →  0  ∈  ( 0 ... 𝐸 ) ) | 
						
							| 75 |  | elfzuz3 | ⊢ ( 𝐸  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) )  →  ( ♯ ‘ 𝑊 )  ∈  ( ℤ≥ ‘ 𝐸 ) ) | 
						
							| 76 |  | eluzfz1 | ⊢ ( ( ♯ ‘ 𝑊 )  ∈  ( ℤ≥ ‘ 𝐸 )  →  𝐸  ∈  ( 𝐸 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 77 | 40 75 76 | 3syl | ⊢ ( 𝜑  →  𝐸  ∈  ( 𝐸 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 78 |  | eluzfz2 | ⊢ ( ( ♯ ‘ 𝑊 )  ∈  ( ℤ≥ ‘ 𝐸 )  →  ( ♯ ‘ 𝑊 )  ∈  ( 𝐸 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 79 | 40 75 78 | 3syl | ⊢ ( 𝜑  →  ( ♯ ‘ 𝑊 )  ∈  ( 𝐸 ... ( ♯ ‘ 𝑊 ) ) ) | 
						
							| 80 | 15 74 40 30 77 79 | swrdrndisj | ⊢ ( 𝜑  →  ( ran  ( 𝑊  substr  〈 0 ,  𝐸 〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ∅ ) | 
						
							| 81 | 72 80 | eqtrd | ⊢ ( 𝜑  →  ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ∅ ) | 
						
							| 82 |  | incom | ⊢ ( ran  〈“ 𝐼 ”〉  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  ran  〈“ 𝐼 ”〉 ) | 
						
							| 83 | 44 | ineq2d | ⊢ ( 𝜑  →  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  ran  〈“ 𝐼 ”〉 )  =  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  { 𝐼 } ) ) | 
						
							| 84 |  | swrdrn2 | ⊢ ( ( 𝑊  ∈  Word  𝐷  ∧  𝐸  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) )  ∧  ( ♯ ‘ 𝑊 )  ∈  ( 0 ... ( ♯ ‘ 𝑊 ) ) )  →  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ⊆  ran  𝑊 ) | 
						
							| 85 | 15 40 60 84 | syl3anc | ⊢ ( 𝜑  →  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ⊆  ran  𝑊 ) | 
						
							| 86 | 85 | ssrind | ⊢ ( 𝜑  →  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  { 𝐼 } )  ⊆  ( ran  𝑊  ∩  { 𝐼 } ) ) | 
						
							| 87 | 86 51 | sseqtrd | ⊢ ( 𝜑  →  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  { 𝐼 } )  ⊆  ∅ ) | 
						
							| 88 |  | ss0 | ⊢ ( ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  { 𝐼 } )  ⊆  ∅  →  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  { 𝐼 } )  =  ∅ ) | 
						
							| 89 | 87 88 | syl | ⊢ ( 𝜑  →  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  { 𝐼 } )  =  ∅ ) | 
						
							| 90 | 83 89 | eqtrd | ⊢ ( 𝜑  →  ( ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 )  ∩  ran  〈“ 𝐼 ”〉 )  =  ∅ ) | 
						
							| 91 | 82 90 | eqtrid | ⊢ ( 𝜑  →  ( ran  〈“ 𝐼 ”〉  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ∅ ) | 
						
							| 92 | 81 91 | uneq12d | ⊢ ( 𝜑  →  ( ( ran  ( 𝑊  prefix  𝐸 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  ∪  ( ran  〈“ 𝐼 ”〉  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) )  =  ( ∅  ∪  ∅ ) ) | 
						
							| 93 |  | unidm | ⊢ ( ∅  ∪  ∅ )  =  ∅ | 
						
							| 94 | 93 | a1i | ⊢ ( 𝜑  →  ( ∅  ∪  ∅ )  =  ∅ ) | 
						
							| 95 | 66 92 94 | 3eqtrd | ⊢ ( 𝜑  →  ( ran  ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ∩  ran  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) )  =  ∅ ) | 
						
							| 96 | 3 21 23 56 61 95 | ccatf1 | ⊢ ( 𝜑  →  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) : dom  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) –1-1→ 𝐷 ) | 
						
							| 97 |  | ovexd | ⊢ ( 𝜑  →  ( ( ◡ 𝑊 ‘ 𝐽 )  +  1 )  ∈  V ) | 
						
							| 98 | 7 97 | eqeltrid | ⊢ ( 𝜑  →  𝐸  ∈  V ) | 
						
							| 99 |  | splval | ⊢ ( ( 𝑊  ∈  dom  𝑀  ∧  ( 𝐸  ∈  V  ∧  𝐸  ∈  V  ∧  〈“ 𝐼 ”〉  ∈  Word  𝐷 ) )  →  ( 𝑊  splice  〈 𝐸 ,  𝐸 ,  〈“ 𝐼 ”〉 〉 )  =  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 100 | 4 98 98 19 99 | syl13anc | ⊢ ( 𝜑  →  ( 𝑊  splice  〈 𝐸 ,  𝐸 ,  〈“ 𝐼 ”〉 〉 )  =  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 101 | 8 100 | eqtrid | ⊢ ( 𝜑  →  𝑈  =  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 102 | 101 | dmeqd | ⊢ ( 𝜑  →  dom  𝑈  =  dom  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) ) | 
						
							| 103 |  | eqidd | ⊢ ( 𝜑  →  𝐷  =  𝐷 ) | 
						
							| 104 | 101 102 103 | f1eq123d | ⊢ ( 𝜑  →  ( 𝑈 : dom  𝑈 –1-1→ 𝐷  ↔  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) : dom  ( ( ( 𝑊  prefix  𝐸 )  ++  〈“ 𝐼 ”〉 )  ++  ( 𝑊  substr  〈 𝐸 ,  ( ♯ ‘ 𝑊 ) 〉 ) ) –1-1→ 𝐷 ) ) | 
						
							| 105 | 96 104 | mpbird | ⊢ ( 𝜑  →  𝑈 : dom  𝑈 –1-1→ 𝐷 ) |