Metamath Proof Explorer
		
		
		
		Description:  A constructed ring is a structure.  (Contributed by Mario Carneiro, 28-Sep-2013)  (Revised by Mario Carneiro, 29-Aug-2015)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypothesis | rngfn.r |  | 
				
					|  | Assertion | rngstr |  | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rngfn.r |  | 
						
							| 2 |  | 1nn |  | 
						
							| 3 |  | basendx |  | 
						
							| 4 |  | 1lt2 |  | 
						
							| 5 |  | 2nn |  | 
						
							| 6 |  | plusgndx |  | 
						
							| 7 |  | 2lt3 |  | 
						
							| 8 |  | 3nn |  | 
						
							| 9 |  | mulrndx |  | 
						
							| 10 | 2 3 4 5 6 7 8 9 | strle3 |  | 
						
							| 11 | 1 10 | eqbrtri |  |