Metamath Proof Explorer
		
		
		
		Description:  Commutation law for triple conjunction.  (Contributed by NM, 21-Apr-1994)
     (Revised to shorten 3anrot by Wolf Lammen, 9-Jun-2022.)
		
			
				
					|  |  | Ref | Expression | 
				
					|  | Assertion | 3ancomb |  | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | df-3an |  | 
						
							| 2 |  | 3anan32 |  | 
						
							| 3 | 1 2 | bitr4i |  |