| Step | Hyp | Ref | Expression | 
						
							| 1 |  | unfilem1.1 | ⊢ 𝐴  ∈  ω | 
						
							| 2 |  | unfilem1.2 | ⊢ 𝐵  ∈  ω | 
						
							| 3 |  | unfilem1.3 | ⊢ 𝐹  =  ( 𝑥  ∈  𝐵  ↦  ( 𝐴  +o  𝑥 ) ) | 
						
							| 4 |  | ovex | ⊢ ( 𝐴  +o  𝑥 )  ∈  V | 
						
							| 5 | 4 3 | fnmpti | ⊢ 𝐹  Fn  𝐵 | 
						
							| 6 | 1 2 3 | unfilem1 | ⊢ ran  𝐹  =  ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) | 
						
							| 7 |  | df-fo | ⊢ ( 𝐹 : 𝐵 –onto→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 )  ↔  ( 𝐹  Fn  𝐵  ∧  ran  𝐹  =  ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) ) ) | 
						
							| 8 | 5 6 7 | mpbir2an | ⊢ 𝐹 : 𝐵 –onto→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) | 
						
							| 9 |  | fof | ⊢ ( 𝐹 : 𝐵 –onto→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 )  →  𝐹 : 𝐵 ⟶ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) ) | 
						
							| 10 | 8 9 | ax-mp | ⊢ 𝐹 : 𝐵 ⟶ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) | 
						
							| 11 |  | oveq2 | ⊢ ( 𝑥  =  𝑧  →  ( 𝐴  +o  𝑥 )  =  ( 𝐴  +o  𝑧 ) ) | 
						
							| 12 |  | ovex | ⊢ ( 𝐴  +o  𝑧 )  ∈  V | 
						
							| 13 | 11 3 12 | fvmpt | ⊢ ( 𝑧  ∈  𝐵  →  ( 𝐹 ‘ 𝑧 )  =  ( 𝐴  +o  𝑧 ) ) | 
						
							| 14 |  | oveq2 | ⊢ ( 𝑥  =  𝑤  →  ( 𝐴  +o  𝑥 )  =  ( 𝐴  +o  𝑤 ) ) | 
						
							| 15 |  | ovex | ⊢ ( 𝐴  +o  𝑤 )  ∈  V | 
						
							| 16 | 14 3 15 | fvmpt | ⊢ ( 𝑤  ∈  𝐵  →  ( 𝐹 ‘ 𝑤 )  =  ( 𝐴  +o  𝑤 ) ) | 
						
							| 17 | 13 16 | eqeqan12d | ⊢ ( ( 𝑧  ∈  𝐵  ∧  𝑤  ∈  𝐵 )  →  ( ( 𝐹 ‘ 𝑧 )  =  ( 𝐹 ‘ 𝑤 )  ↔  ( 𝐴  +o  𝑧 )  =  ( 𝐴  +o  𝑤 ) ) ) | 
						
							| 18 |  | elnn | ⊢ ( ( 𝑧  ∈  𝐵  ∧  𝐵  ∈  ω )  →  𝑧  ∈  ω ) | 
						
							| 19 | 2 18 | mpan2 | ⊢ ( 𝑧  ∈  𝐵  →  𝑧  ∈  ω ) | 
						
							| 20 |  | elnn | ⊢ ( ( 𝑤  ∈  𝐵  ∧  𝐵  ∈  ω )  →  𝑤  ∈  ω ) | 
						
							| 21 | 2 20 | mpan2 | ⊢ ( 𝑤  ∈  𝐵  →  𝑤  ∈  ω ) | 
						
							| 22 |  | nnacan | ⊢ ( ( 𝐴  ∈  ω  ∧  𝑧  ∈  ω  ∧  𝑤  ∈  ω )  →  ( ( 𝐴  +o  𝑧 )  =  ( 𝐴  +o  𝑤 )  ↔  𝑧  =  𝑤 ) ) | 
						
							| 23 | 1 19 21 22 | mp3an3an | ⊢ ( ( 𝑧  ∈  𝐵  ∧  𝑤  ∈  𝐵 )  →  ( ( 𝐴  +o  𝑧 )  =  ( 𝐴  +o  𝑤 )  ↔  𝑧  =  𝑤 ) ) | 
						
							| 24 | 17 23 | bitrd | ⊢ ( ( 𝑧  ∈  𝐵  ∧  𝑤  ∈  𝐵 )  →  ( ( 𝐹 ‘ 𝑧 )  =  ( 𝐹 ‘ 𝑤 )  ↔  𝑧  =  𝑤 ) ) | 
						
							| 25 | 24 | biimpd | ⊢ ( ( 𝑧  ∈  𝐵  ∧  𝑤  ∈  𝐵 )  →  ( ( 𝐹 ‘ 𝑧 )  =  ( 𝐹 ‘ 𝑤 )  →  𝑧  =  𝑤 ) ) | 
						
							| 26 | 25 | rgen2 | ⊢ ∀ 𝑧  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( ( 𝐹 ‘ 𝑧 )  =  ( 𝐹 ‘ 𝑤 )  →  𝑧  =  𝑤 ) | 
						
							| 27 |  | dff13 | ⊢ ( 𝐹 : 𝐵 –1-1→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 )  ↔  ( 𝐹 : 𝐵 ⟶ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 )  ∧  ∀ 𝑧  ∈  𝐵 ∀ 𝑤  ∈  𝐵 ( ( 𝐹 ‘ 𝑧 )  =  ( 𝐹 ‘ 𝑤 )  →  𝑧  =  𝑤 ) ) ) | 
						
							| 28 | 10 26 27 | mpbir2an | ⊢ 𝐹 : 𝐵 –1-1→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) | 
						
							| 29 |  | df-f1o | ⊢ ( 𝐹 : 𝐵 –1-1-onto→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 )  ↔  ( 𝐹 : 𝐵 –1-1→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 )  ∧  𝐹 : 𝐵 –onto→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) ) ) | 
						
							| 30 | 28 8 29 | mpbir2an | ⊢ 𝐹 : 𝐵 –1-1-onto→ ( ( 𝐴  +o  𝐵 )  ∖  𝐴 ) |