Metamath Proof Explorer
		
		
		
		Description:  Elements in the symmetric group are 1-1 onto functions.  (Contributed by SO, 9-Jul-2018)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | symgbas.1 | ⊢ 𝐺  =  ( SymGrp ‘ 𝐴 ) | 
					
						|  |  | symgbas.2 | ⊢ 𝐵  =  ( Base ‘ 𝐺 ) | 
				
					|  | Assertion | symgbasf1o | ⊢  ( 𝐹  ∈  𝐵  →  𝐹 : 𝐴 –1-1-onto→ 𝐴 ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | symgbas.1 | ⊢ 𝐺  =  ( SymGrp ‘ 𝐴 ) | 
						
							| 2 |  | symgbas.2 | ⊢ 𝐵  =  ( Base ‘ 𝐺 ) | 
						
							| 3 | 1 2 | elsymgbas2 | ⊢ ( 𝐹  ∈  𝐵  →  ( 𝐹  ∈  𝐵  ↔  𝐹 : 𝐴 –1-1-onto→ 𝐴 ) ) | 
						
							| 4 | 3 | ibi | ⊢ ( 𝐹  ∈  𝐵  →  𝐹 : 𝐴 –1-1-onto→ 𝐴 ) |