Metamath Proof Explorer
		
		
		
		Description:  .~ is a relation.  (Contributed by Alexander van der Vekens, 25-Mar-2018)  (Revised by AV, 30-Apr-2021)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | erclwwlkn.w |  | 
					
						|  |  | erclwwlkn.r |  | 
				
					|  | Assertion | erclwwlknrel |  | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | erclwwlkn.w |  | 
						
							| 2 |  | erclwwlkn.r |  | 
						
							| 3 | 2 | relopabi |  |